Why Is My uPVC Window Not Closing Properly? - Dengarden - Home and Garden
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Why Is My uPVC Window Not Closing Properly?

Author:

I've been writing on DenGarden for over 5 years and have over 25 years of experience working in the window and door trade.

Gap in window where hinge won't close sash fully.

Gap in window where hinge won't close sash fully.

How to Check for Problems in Your uPVC Windows

The most common problem with PVC windows is that the sash won't close properly against the seal, which means you will lose money when the heat escapes outside. The problem is caused either with the lock, the hinges, or a dropped sash.

Check Hinges

Close your sash and check the hinge side. If there is a gap between the sash and the frame on the hinge side, then it is your hinges. All that is wrong is that your hinges are after wearing down and not pulling the sash in tight against the frame anymore. A new pair of hinges is needed. It only takes a few minutes and is not a big job, most people would be able to do this job themselves, and most window companies will do it for you.

Check Lock

Close your sash, and on the inside, slide a credit card between the sash and the frame. The card should fit tight and shouldn't be easy to move around. If not, then you more than likely are getting a draft. All that is needed here is a small adjustment to your lock and it will tighten up the seal. Almost anyone would be able to do this job; all that is needed is a set of Allen keys.

Check If Sash Has Dropped

This problem affects windows that have a side-swing opening, the type that opens like a door. Close your sash and look at the top corner above the handle. Move slightly; if you can see daylight, that means the sash has dropped. Also, check that the sash is fitting equally with the frame. If it has shifted down at the handle side, then your sash may be dropping. Most sashes will drop a bit without affecting the overall performance of the window, but if it keeps dropping, that is when the problems start.

Espag lock showing the cams which can be adjusted to tighten the seal.

Espag lock showing the cams which can be adjusted to tighten the seal.

Check the seal with a credit card. It should fit tight and be hard to move.

Check the seal with a credit card. It should fit tight and be hard to move.

How to Fix a uPVC Window That's Not Closing Properly

If you want to have a go at fixing any of these problems yourself, below is a guide to help you get it sorted.

How to Fix uPVC Window Hinges:

  1. Unscrew the hinges from the frame and lift the sash out.
  2. Have a look at the sash and the way the old hinges are fixed to it.
  3. Unscrew the old hinges and put the new ones on it the same place.
  4. Place the sash back into the frame and screw the hinges back onto the frame.
  5. Check that it is opening and closing.

How to Fix uPVC Window Locks:

To adjust the lock will only take a minute, and all that is needed is an Allen key.

  1. Open the window and look at the cams—these are the parts that move up and down when you move the handle.
  2. These can be turned with an Allen key. Turn them one way and it tightens the sash against the seal. Turn them the other way and it loosens them.

How to Fix a Dropped Sash in a uPVC Window:

  1. Take out the glass, then close your sash and make sure your sash is lined up.
  2. Now put your glass back in and pack it right around with plastic packers so that there is no movement between the glass and the sash. If you don't have plastic packers, you can get them at any company that makes windows. They are very cheap to buy. The chances are there is not enough of them in your sash from day one and that is why your sash dropped.
  3. To help prolong the life of your Espag locks and hinges—especially if you are living near the sea—rub grease onto them. This will keep the air from harming them, stop corrosion, and slow down wear and tear. As for the dropped sash, there is nothing you can do about this until it happens, as this happens due to the glass being fitted badly.

Feel free to ask any questions by posting them in the comment box below.

More Help With uPVC Windows

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

Questions & Answers

Question: My side-swing window was working fine one day, but now will not close all the way, how can I fix this?

Answer: Sounds like you just need a new pair of hinges. Not a big job and not very expensive to get a pro to do it. If you are going doing it your self you will need to change both hinges and not just one.

Question: My window doesn't close properly at the top. I've tried fitting new hinges but it's just the same there's a draft blowing through all the time. Is my window just cheap uPVC windows?

Answer: If this is a side hung sash and if the draft is coming in on the hinge side at top.

It sounds like the hinges are fitted wrong or they are the wrong size.

If the draft is coming in at the top on the lock side.

Check the locking cam is at most six inches away from top.

If it is more than six inches away than you will need to fit a longer lock.

If the lock is the correct size than check if the sash is after dropping down.

If this is the case you will need to take the glass out and redo the toe and heeling to get the window sash back in place.

If you have a top opening sash and the draft is coming in at the top in the center.

Than it sounds like the inter locker is missing.

A inter locker is just a set of two wedges that keeps the sash closed tight when it is closed.

Question: One of my top hung windows is not sealing properly against the frame and letting in some draft. If I pull the window hard towards myself when shutting the window, it closes a bit better but not completely. What could this be?

Answer: You might just need a new pair of hinges.

Question: I have adjusted a small upvc window, so it closes tighter on the lock side, but how do I adjust the window so it closes tighter on the hinge side, as I can clearly see that the rubber seal is barely compressed?

Answer: Open your window and look straight in at the studs that go into the keep. These will take an Allen key. Just turn these. As they are set of center. So when you turn one way it will tighten on to the seal, and turn the other way to loosen of the seal.

Question: I recently moved into a new building, and my bedroom window does not seal properly at the top right corner. I’ve tried adjusting the cams, but that doesn’t seem to work. Do you have any suggestions?

Answer: Your window needs new hinges.

The interlocking part on the hinge is worn down and not closing the window against the seal.

Be sure to change both hinges and not just the faulty one because if you don't, your sash will not run smoothly and will only cause your hinges to fail again.

Question: The locking pins on my top hung sash window are catching on the bottom edge of the frame. The window is relatively large about 1.5m high x 1.2m wide and relatively heavy.  I recently had the hinges replaced but this has not solved the issue, could it be that the window has dropped? Do I need to check the packing or could it be a further issue with the hinges?

Answer: Yes it's the hinges. A sash that big will always drop a bit, which must be allowed for when fitting hinges. But it's only a matter of readjusting the hinges to get it right.

Question: I can push my window open when closed but have noticed the handle does not go down fully to a closed position. Could this be the sash?

Answer: It sounds like the espage lock is broken. This is the locking mechanism inside the window which the handle goes into. The backset is after breaking, and the handle will not operate the locking system. But there is some good news the fact that your window is open it makes it very easy to replace and can be done in a matter of minutes.

To take out espage lock just take off your handle first, then with the window open look into the side and you will see the espage lock running the length of the sash. Unscrew this, and your lock will then come out.

To fit new one just do the same in reverse.

Question: I've replaced hinges on side hung upvc window. Now when I close the window I've got a big gap between sash and window frame on the bottom corner of the handle side. All other sides are ok. Do you have any suggestions? How to fix this problem.?

Answer: It sounds like the sash is hanging off the square and it is now hitting the run-up wedge on the bottom.

Check the bottom of the window frame and remove the block. If this works you will then need to re-adjust your sash and then replace the block

If this doesn't work check that both hinges are the same top and bottom. They might look the same, but they can run different

Question: I have a top opening window that I cannot lock. When the window is closed and handle in the lock position I can still push it open. What could this be?

Answer: You need a new espage lock. This is the part that fits inside your window.

In your window, the backset is broken. So when you turn the handle it won't move the locking cams Into the locked position. Not a big job and any window repair company will be able to fix it in about ten minutes

Question: The glass unit in the inner part of the UPVC window frame has dropped down on one corner. Is it lack of packers when they have put the glass in?

Answer: You are 100 percent right.

The only way the double glazed unit can move in the frame, is if there is not enough packers around it to keep it from moving.

Plus if there is no packers on the bottom and glass is sitting on the frame it can break down the seal in the double glazing over time. As the bottom of the window frame is designed to take the flow of any water that gets inside the window seal back out to the front and out the drainage holes on the outside of window. So if glass is sitting on frame it can obstruct this flow. Plus it means the double glazing seal is sitting in water all the time.

To fix this problem you need to take glass out and repack the double glazed unit.

If this unit is one of the fixed panes and not sash than all you need is packers on the bottom so its not sitting on the window frame.

But if the glass is in a window sash (opening) than you will need to pack it right around to stop all movement. To do this take glass out than close window sash and make sure it is hanging in the right position. If sash is sagging down in one side make sure you line it back up before you repack window.

Question: Do you have any tips for replacing the hinges on a side hung window? I think I damaged my first hinges when re-attaching the sash after installing trickle vents.

Answer: Fix hinges to sash first than slot the sash in with the hinges in the open position. Once you do one set it'll get easier.

Why take sash out to fit trickle vents. You can fit them with the sash in position.

Question: We have a PVC sliding sash window and the top half that opens out has been damaged in a storm. The hinges have become misshapen. Is it possible to buy a new set of hinges only?

Answer: The best thing to do is take a few photos of hinges and window and go to a local window supplier they should be able to tell what gear you need. As there is a lot of different types of hinges. A lot will look the same but they come in different stack heights plus you have side and top hung style.

The standard casement window is straightforward. But some of the sliding sash windows can be quite tricky

Question: In the night vent position the mushroom cams on my side hung windows are going into the keep slots on the top and bottom keeps but is not going into the keep slot on the middle one as the top of the cam is pressing on the top of the keep?

Answer: If you mean it's hitting on the upward motion. Than get a alan key and adjust the cam in wards or out wards. If you mean it's running out side the cam and not even catching the cam. Than take of the keep and put a washer behind it to bring it closer. Or tap the frame outwards with a mallet as it could of moved away with the pull of the handle over time

Question: How do I know what size hinges I need?

Answer: You don't. The new hinges come with spacers. So you can add or remove them to suit your door

Question: My window will lock ok in night vent position but when I pull it fully closed the handle will only go 3/4 of the way to lock position, any tips?

Answer: Sounds like the cam is hitting the keep. Best thing to do is take one keep of than see will it work. If not take another keep off. Then just keep going till you find which one is given the trouble. When you find which one all you got to do then is replace it into the correct position

Question: My windows seem to be draughty and I suspect the interlocks are to blame. Looking at them I don’t understand how they can lock and seem to be a mix of types. One is is metal style and the other plastic and they seem to push against each other but push apart rather thank lock together. Have they been fitted the wrong way around?

Answer: Interlocks come in all shapes plus you have different types for different styles of hinges. But they all do the same job and when the window sash is closed. They should work like two wedges one on the sash and one on the frame, and when closed they keep the center part of the sash tight against the frame. BUT as windows get older hinges will start to wear down and your window sash can than run in a different line. So this can also affect the way your interlockers meet.

Here's how to tell.

If your windows were fine all along, then started letting drafts in. More than likely it's your hinges.

But if your windows have been giving trouble from day one. Then it is more than likely the interlocks. They might be fitted wrong, or they could have the wrong style to match your hinges.

Note: The egress fire hinge for side hung window sashes are different from a top hung window sash as the hinges run in different lines and close differently.

So if someone mix these up when making the windows, they would not allow the window sash to close properly

© 2012 Martin

Comments

Crystal on June 27, 2020:

Hi,

My window handle seems to move and be working fine when the window is open but as soon as I close the window to lock it the handle seems to get stuck and I have to really pull it into the frame and use some force to pull the handle down to lock it. (Almost as if the lock alignment isn't quite right?) The window is a side swing window with the hinges on the left and the handle on the right. Please could anyone advise on how to fix this issue?

Many thanks in advance!

Crystal on June 27, 2020:

Hi,

My window handle seems to move and be working fine when the window is open but as soon as I close the window to lock it the handle seems to get stuck and I have to really pull it into the frame and use some force to pull the handle down to lock it. (Almost as if the lock alignment isn't quite right?) The window is a side swing window with the hinges on the left and the handle on the right. Please could anyone advise on how to fix this issue?

Many thanks in advance!

Charlotte Hajek on April 20, 2020:

Hello,

I have a top hung window which isn't closing properly, it seems to have about an inch gap when it's closed at the top and round to the right of it. Could you advise what you think might be the issue please

Martin (author) from Ireland on January 02, 2020:

C Hague - It sound like your window is a side opening sash. If this is the case and your hinges are on the left and you still have a gap on the the top right of sash. Than it just means your sash is after sagging down wards. To fix this the beading needs to come out and sash needs to be Toe & heeled. This is when the sash is lined up correctly and the glass is than pack tightly to the sash. So there can be no more movement. Its not a big job and could be done in about ten minutes.

C Hague on January 02, 2020:

Hi

I've noticed that the top right hand corner of my window still has a slight gap when shut.

The hinge is on the left side.

Can you help.

Cheers

Helen on November 05, 2019:

Hi martin forgot to say that the handle won't move either now. Should've just not cleaned them ha ha. Thanks again Helen

Helen on November 05, 2019:

Hi martin thanks for your quick reply unfortunately the room is up high I can't get to the outside of it. I've managed to put it on the little clip thing if you know what I'm talking about. Will it be expensive to fix. Thanks again Helen

Martin (author) from Ireland on November 05, 2019:

To Helen - Sounds like you need a new pair of hinges. To get it closed for now . Go to the outside of window and open it about half way. Than push on the hinge side of the sash while you are closing the sash. This will get the hinges to engage again and allow your window to close fully.

Helen on November 05, 2019:

My window after cleaning it on the outside won't close completely why is this. I get it to the point that it is ajar if you know what I mean difficult to explain. Can anyone help urgently thanks

Tim on October 15, 2019:

My window will not close because the locking beads/mushrooms along the espagnolette now only slide halfway up (and therefore do not engage the fixings on the frame. I have bought a new handle but the mechanism still only slides up half way. Any suggestions?

Martin (author) from Ireland on October 05, 2019:

First thing to try is this. Open the sash like a door to 90 frgtrs or more. Than on the top of the sash on the hinge side look at the end you will seek a hex nut. Turn this one way and it will pull the whole sash back which will than lift your bottom corner up on the handle side.

Than if you still need more adjustment. Close your sash and on the bottom at the hinge side. Look at the part of the hinge that you can see. There is a pvc cap which can slide up and come of. Once you have this taken of look down into the hinge and you will see a hex nut. Thurn this clockwise and the whole sash will lift upwards.

At Andrew on October 02, 2019:

First thing to try is this. Open the sash like a door to 90 frgtrs or more. Than on the top of the sash on the hinge side look at the end you will seek a hex nut. Turn this one way and it will pull the whole sash back which will than lift your bottom corner up on the handle side.

Than if you still need more adjustment. Close your sash and on the bottom at the hinge side. Look at the part of the hinge that you can see. There is a pvc cap which can slide up and come of. Once you have this taken of look down into the hinge and you will see a hex nut. Thurn this clockwise and the whole sash will lift upwards.

Andob on October 02, 2019:

Hi, i'm hoping someone can help, I have pvc tilt turn windows, the ones that can open like doors as well as just tilt and open at the top. One of them it won't shut properly. The piece of metal that sticks out the lower handle side of the window hits into the part its meant to connect with in the frame, any ideas? Further to this, when opening with just it tilted towards me (so just the top is open) the lower right corner (same corner as above) does not lock into the frame and the window is only connected to the frame by the lower left hinge. I'm aware both are related to the lower right window/frame connection, can anyone advise how to adjust it? I'm handy with tools so would rather not have to fork out for someone else to do it for me. Window is 3 floors high, so can't access from the outside.

Thanks everyone in advance.

Andrew

Martin (author) from Ireland on July 05, 2018:

Colin Somerville - It sounds like the screws belong to the hinge part that slide up and down which when tightened they will slow down the movement of the sash. If you look at the center of the hinge there should be a black plastic runner which will take these screws

Colin Somerville on July 05, 2018:

How do I relocate and fix two screws that have come out of the locking sliding mechanism on the side of the frame?

They are old weatherseal Windows. When located they are supposed to stick out by about two mm from the frame mechanism.

mark on June 23, 2018:

i would not trust someone who calls a casment window a sash they are totally different and have different problems

Chris on March 15, 2018:

Hi, I have a top hung window which, when closed I can see a gap at the bottom of the window (handle side).

The seals look intact and the hinges move freely, is it possible to adjust the window to move down on the hinge?

Thanks

Martin (author) from Ireland on March 12, 2018:

Need a small bit more info Mike about the door like is it the hing side or lock side or where is the gap

Martin (author) from Ireland on September 09, 2016:

Sounds like the glass was not packed properly to the sash. To fix will mean taking glass out. Than line sash up properly. Replace glass and pack glass right around with plastic glass packers. This is know as toe & healing once done properly your window sash should not drop down no more

keith pell on September 09, 2016:

indow wont close smoothly,it has a plastic ride up piece on the interior of the frame that can slide about,I have tried moving this along but window still not closing properly, any advice please. Keith Pell

Larisa on October 09, 2015:

Hi Martin, thank you for your article.

I have a window with 2 side hinges. The right side is fine but there is a little gap in the left bottom corner. When I compared the sides, I saw that on the right there is a small plastic part which keeps that bottom corner tightly closed. On the left side, however, it is missing. It is not a surprise that it is missing given that this part is not glued or anything, it is just kind of inserted there and you can take it away easily. So, now I need a replacement for it, the only problem is that I don't know how this part is called. Maybe you can tell me?

I've just moved into this apartment and not sure yet if the landlord would be able to help. At least I can take that part from the right side and make a copy somewhere, not sure where exactly though, any ideas? Or is just easier to change the hinge? Do you think it would come with that part? If so that would be the simplest thing to do.

Martin (author) from Ireland on April 24, 2014:

Once they hit together when the window closes they should be fine. Plus what happens sometimes fitters put the wrong ones on. A side hung sash has different type interlockers compared to a top hung sash.

Martin on April 24, 2014:

Thanks for your reply, my windows do have the wedges fitted, just checked, should they align with each other or should they be overlapping? Mine don't seem to be aligned, they are both fitted, but slightly apart? Is that right or should they align. Cheers

Martin (author) from Ireland on April 24, 2014:

If there is no gap out by the hinges. Than your hinges are fine. But if you have a gap by hinges than you just need a new pair of hinges and this will more than likely sort out gap in center. But if hinges are fine you may need a pvc interlocker fitted. This is like two pvc wedges one is fitted to frame and the other to the sash and when you close your window they lock together to get a tight seal. They are used on bigger sashs. They are cheap to buy and very easy to fit. But you will find in some cases that one window company interlockers, will not fit another window company window. So if you can, go back to where you got your windows and ask for some window interlockers. If they are any good they should give you some for nothing as they cost next to nothing.

Mark on April 24, 2014:

Hi Martin , I've got an air gap and a draught coming threw my living room window, it is a half n half window which opens from the bottom out wards. At the top of the window, in the middle, there is a small gap between the frame and actual window casing inside, is this a fault or can it be tightened up???

Martin (author) from Ireland on March 26, 2014:

There is a lot of different ways to get air moving in a room if you google it you will find many. But the best ways are to bring some fresh air in from the outside. That's why all building regs require vents should be fitted into walls or windows.

Chandru on March 26, 2014:

Hi martin,

I used small fan, since i don't have air vent on opposite side except door. The room gets little hotter compared to the previous method. But initially the fan air causes some cooling.

Martin (author) from Ireland on March 25, 2014:

All you need do is get the air moving in the room. This is done by adding an air vent on the other side of the room which will allow cooler air in. The cooler air will than move across the lower part of the room towards the heat which will than push the warmer air across the top. If you are not able to fit a vent. Some people use a small fan to move the air around. But the best option is to get cooler air in from outside. If you already have vents fitted to your walls than check and make sure they are not blocked.

chandru on March 24, 2014:

Dear Martin,

My heaters are located deep inside the window slab. I hope this is causing the problem of increasing humidity.

Could you tell me, what can i do to bring this heat air to bring out from the window slap? Any duct?

Martin (author) from Ireland on March 05, 2014:

If your window is 1400 tall and a side opening it should have interlockers. The 700mm he is on about is the distance from one hinge to another it don't' matter if it is on the width or height. Plus when you buy windows and doors you have a five year consumer guarantee by law. So if your hinges are failing after only a few months. You should get everyone of them inspected as there is something wrong.

lomond on March 05, 2014:

Just to update you.

Polyframe just been. lovely cold and wet so window not doing it. . typical!. however he Will supply the interlock wedges to see if that solves it but as a company they usually only supply them on windows over 700 wide (mine are only 510, 1400 tall) as the hinges are reinforced so not required. Frames come with 10year guarantee but hard wear only 12months. So once these are fitted hopefully my problem Will disappear.

Martin (author) from Ireland on March 04, 2014:

All PVC systems worldwide use interlockers. Just ask your supplier what Pvc system they are using than ring the maker and ask about interlockers. Plus all moving parts on a window have a two year warranty that means your hinges are covered.

lomond on March 04, 2014:

Thank you, New windows don't have the interlockers i presumed due to advances in window design. Spoke with manufacturer who say they don't fit or supply them as they use strong enough hinges as standard which eliminates the need (beg to differ). Builder who ordered and installed them was to come out to have a look but hasn't so may need to find a repairing firm that Will fit them for me. I really enjoyed your post and am grateful to you for your advice.

Martin (author) from Ireland on March 03, 2014:

Sounds like there is no interlockers on the openings. These are two angle Pvc wedges. If you open the window and look at the hinge side there should be one on the frame and the other on the window sash. When you close your window these two pieces interlock and keep it tight against the seal. Without them your hinges can wear down very fast. The reason you are seeing the gap at certain times is because PVC can expand and contract by up to 7mm in hot and cold weather But your PVC interlockers should keep everything in place. Your windows should of come with these interlockers fitted and if they are fitted they must be fitted wrong. Go back to the person who sold you the windows and get them to fit them. Plus check out your hinges now because they may have excess wear and tear.

lomond on March 03, 2014:

I had New windows installed 4 months ago and have recently noticed the road traffic again. on inspection could slot a shopping trolley coin in the gap at the hinge side but only in the middle. i opened and shut the window for it to disappear (or that's what i thought). this mornin at 8am i could again here the traffic as if the window had been left on latch but again this gap had appeared (between the window and frame) so i knew i hadn't opened it etc since last time it opened so went out leaving it as it was only to come back at 11 and it has mysteriously closed. . . any ideas? surely not the weather (cold overnight to warm and sunny am)

Martin (author) from Ireland on February 20, 2014:

The window keeps need to be moved up a small piece. The keeps are the parts on the frame the window lock onto. The problem is when the window is closed and you close the handle the cams are hitting the top of the keeps. Which won't let you close handle fully. When you have window is open a small piece and you close the handle the window sash is able to move down and allow the handle to close. If you open you window sash than operate the handle and look at the movement of the cams you will see what I mean.

Sam on February 20, 2014:

Hello, my window will fully lock on the second setting (so slightly open) but the handle will not lock into position when fully closing the window. I've swapped the handles as someone suggested that might be the issue, however that has made no difference, the handle works fine on other windows. Any suggestions?

Tim on February 04, 2014:

Great info on sorting pvc windows

Martin (author) from Ireland on January 24, 2014:

What you need is someone to look at it for you. Because there are so many different ways that could be causing this. But it sounds like to me that you need to upgrade to a new to upgrade to a new window. And if its -9degress outside. I think it would be worth your while pay the bit extra and get Triple Glazing with low-e Glass.

Chandru on January 24, 2014:

Yesterday i closed all blinds and slept. Outside temperature was -9deg., still i get condensation a lot in my windows..... But the humidity was less around 51%.

So when i open the blinds and sleep i see reduce in temperature and less condensation on glass edges. If i close the blind, no reduce in temperature but lot of condensation..... So from this any one can give me some solution ?

Chandru on January 23, 2014:

Ya water is not coming., now the temperature is -6 deg and snowing... so this condensation is occurring due to insulation of double glazing failure?

Martin (author) from Ireland on January 23, 2014:

That sound like condensation not water coming in through window

chandru on January 23, 2014:

Dear martin,

As i said the there is no water between my glass panes.

I see water in interior of the glass at lower edges.

If the insulating glass seal fails this vl occur or some other reason for it?

Martin (author) from Ireland on January 23, 2014:

Yes if the double glazing Breaks down condensation is between the the two panes, and you won't be able to clean it.

Note : If water is coming in through window you will see a build up of water on window board. It will NOT just appear as condensation.

Chandru on January 23, 2014:

One question i like to ask you, if the insulating glass seal fails, condensation occurs between double panes or interior of glass edges?

Chandru on January 22, 2014:

Yesterday, in my place we had -4deg C and it is too dry. I had open all the windows for 15mins. then my room humidity came down to 36%. And after that i have not used curtain or blinds., i slept in morning again it went up to 59% and light drops of condensation at the lower edge of the windows.

I m trying to find some more methods... and let me update here....

Martin (author) from Ireland on January 22, 2014:

If you find out what is causing it. Let us know it might help someone else out

chandru on January 22, 2014:

Ok, even my friends here are also saying the same., one of my friend want to visit my house to find the cause of it...

Martin (author) from Ireland on January 22, 2014:

The damp air is coming from somewhere, it is only a matter of finding what is causing it. You could hire an engineer he will tell you what is causing the problem. But they can cost a lot of money. Here are some causes that people don't think off. Too many plants in the house. Drying clothes in rooms.

It can be very hard to pinpoint what is causing condensation. That is why sometimes you need an engineer. They would of come across almost everything, and most can tell just by walking around the house inside and out

Chandru on January 22, 2014:

The walls are pretty good. But my neighbourhood also using the same, but he doesn't have condensation on his window. In bathroom also i have exhaust fan, during shower it vl b keep running and even after shower also it vl run for about 5mins.

Don't know what more i have to do...?

Martin (author) from Ireland on January 22, 2014:

Bad insulation - Check if you have any condensation on the walls. If you have insulation on walls and floor. Than it is more than likely just a bad window. The older pvc windows only came with standard double glazing. Which was better than single glazed and reduced condensation a small bit. But you will find the newer windows will get rid of the condensation. Unless you have an excess of water in your air. Also if you have a shower nearby remember all that steam is water and it must go somewhere.

Chandru on January 22, 2014:

I am exchanging air often twice a day about 10mins.

What is meant by bad heating ? becos i heat my room all the day in low (16deg C) and in night nearly about 20deg C i keep.

Bad insulation, how should i check this.,

Martin (author) from Ireland on January 22, 2014:

The seal is to stop draughts. If you have a problem with condensation on your windows that is a whole different story. The first thing you should know. Is windows DON'T cause condensation.

Condensation is water in the air. This water is coming from inside your house somewhere. There are three things that will cause condensation. 1- Bad heating 2- Bad air ventilation 3-Bad - Insulation. If you have one of these three things it can cause condensation.

But you can increase your insulation on the window by upgrading your Double Glazing to a Low-E Glass. But it sounds like your window is old and you may be better of getting a new window.

Chandru on January 22, 2014:

Yesterday as you said, i have bought siliconrubber seal (High flexible type) pasted on the existing window seal. But still i see lot of condensation on my window. Also i see the water on the exterior seal top....? Could have any solution for it?

Martin (author) from Ireland on January 21, 2014:

No matter what seal you get, it may not last that long because your hinges will only push out more. Once your hinges start to wear they will keep going. So when you put on the extra seal it will just put a bit more pressure on the hinges. Which will make them wear faster. How long depends on what type of hinges they are. So just buy a cheap seal as you don't know how long it will last. Remember all you are doing is filling a gap. So a 100euro seal will do the same thing as a 5euro seal. The only different will be the glue that is holding it on. But if you do change your hinges sometime this extra seal must come off. Otherwise it will break your new hinges

chandru on January 21, 2014:

So i understand from your message, i can stick an additional onto my existing seal not Frame, am i right? If so, could you recommend me some good material seal which will come for another 6months or so?

Martin (author) from Ireland on January 21, 2014:

You can add more. Most hardware shops will stock a seal which just sticks onto your old seal. This will give you an extra 5mm of a seal. But how long it will last depends on how much your hinges are worn. It might last a week or it might last six months or more. The seal should only cost about 5 to 10 euros. Don't go buying expensive seals as it won't last.

chandru on January 21, 2014:

I need one more clarification, if i have still the air leakage in this corners, can i add additional rubber sealing on the frame.

If so which kind of rubber seal would be better., Any recommendation?

Chandru on January 21, 2014:

Thank you for your immediate reply. Let me check it today and give u feed back.

Martin (author) from Ireland on January 21, 2014:

When adjusting the cam on a lock a half turn should be enough. If you give them a full turn they are only back in same place you started. But watch the cam as you turn it. It should move towards the inside. This will tighten the seal against the frame. If you turn it a half turn the other way it will move away from the inside. This will loosen your seal against the frame.

On the hinge side open the window out, than put some grease on the hinges make sure you get the grease right up into the corners. If this don't work on the hinges you more than likely need new hinges.

chandru on January 21, 2014:

Hello Martin,

I have PVC windows, i have air leak near hinges and also opposite side of the hinges (exactly diagonal to hinges). When i tighten the locks near the handle, it is keep rotating. How should i get rid of the problem. How should i make airtight in my windows? Please help

Martin (author) from Ireland on January 18, 2014:

You can't tighten them. Sounds like the hinges are worn down. You will need a new pair of hinges fitted. If your window is less than two years old the warranty should cover them. As you will find that with most window companies, moving parts only have a two year warranty.

Tru on January 18, 2014:

Hi, ive got upvc windows and would like to know how to tighten the window but mainly where the hinges. The windows are tight on the handles side but not tight enough on the hinges side. I can put a credit card between the rubber seal and the window frame easily. Please help

Dan on January 08, 2014:

Great Info about pvc windows

Martin (author) from Ireland on January 07, 2014:

The window sash has just slipped down on the hinge. This can happen in two places.

But First thing you must do is get your window open. Just use a long screwdriver and prise the sash back upwards. Now you should be able to open the window. Than just put another screw on the hinge to stop it slipping back down. You will have to do this in two places. One were the hinge is fixed to the window frame and the other were the hinge is fixed to the window sash (sash is the part of window that open and closes). Once this is done your window should work fine.

Alex on January 07, 2014:

My window is a bathroom window and opens from the bottom out wards and has a large non opening window below, the top window has dropped slightly on the right side and is therefore stopping it from shutting and it won't move neither forward or back, how do I repair this as my bathroom is freezing all the time and I would love to shut it!

John on December 19, 2013:

Thanks for putting up this information It sorted my pvc window

Martin (author) from Ireland on November 19, 2013:

When adjusting the locks against the seal about a 1/4 turn should do it. You should feel the deferent's in the handle when you close it. Just make sure that you don't loosen it. If you open the window and look at the way it turns it should move towards the outside this will make your seal tighter. If it moves towards the inside it will loosen

Darryl on November 02, 2013:

hi there, very informative article! Thanks for posting. When tightening locks against the seal do you know which direction tightens the seal and roughly how many turns, quarter turns, half turns to initally try? Thanks.

Bill L on October 12, 2013:

thank you, most helpful. Shall prepare for the coming winter! ......cheers

Jake Frost from London, United Kingdom on August 25, 2012:

This is great to know. I will keep it all in mind, you never know when it will come in handy.