Under windows leaking

[RVP]

Hi all!

We moved into a newly renovated Victorian property a couple of years ago. We have water leaking in under the window sills and I'm struggling to find what the issue is. We have sash windows which the developers put in new, so I'm thinking probably a problem with the installation? Any ideas on how to fix or anyone had anything similar?

 

[Cubist]

Check the external joints between the window frames and the wall - all around them 'including the top edge'. Refresh the caulking as needed. Driven rain can be forced around these to appear indoors having 'tracked' along the top edge and sides of the frame beneath the walls exterior surface.

 

[Stevers]

Timber moves with moisture content so can shrink to leave gaps, and as it's a bay window, there's even more scope for gaps.

 

[RVP]

Timber moves with moisture content so can shrink to leave gaps, and as it's a bay window, there's even more scope for gaps.

Thank you! In this case is there much I can do apart from caulking?

 

[RVP]

Check the external joints between the window frames and the wall - all around them 'including the top edge'. Refresh the caulking as needed. Driven rain can be forced around these to appear indoors having 'tracked' along the top edge and sides of the frame beneath the walls exterior surface.

Thank you! That's very helpful, I will try that. I've also seen that some of the paint is already flaking off the window frames which I imagine could also be causing issues?

 

[Cubist]

In this case is there much I can do apart from caulking?

Not really, once the caulking material(s) have been installed properly that will prevent further water penetration and the interior plaster will dry out in a relatively short time. You may however need to do a little painting to cover the remaining stains.

Thank you! That's very helpful, I will try that. I've also seen that some of the paint is already flaking off the window frames which I imagine could also be causing issues?

Old paints will often crack and flake from wooden surfaces in particular - particularly those exposed to weather and strong sunlight. This is due to the frequent expansion and contraction of the wood as the seasons change together with indoor heating. It's always best to keep an eye on it and either make repairs as needed or re-paint the frames completely as desired to limit the negative effects of water absorption.

 

[RVP]

Not really, once the caulking material(s) have been installed properly that will prevent further water penetration and the interior plaster will dry out in a relatively short time. You may however need to do a little painting to cover the remaining stains.

Old paints will often crack and flake from wooden surfaces in particular - particularly those exposed to weather and strong sunlight. This is due to the frequent expansion and contraction of the wood as the seasons change together with indoor heating. It's always best to keep an eye on it and either make repairs as needed or re-paint the frames completely as desired to limit the negative effects of water absorption.

Thank you! All of the windows and frames are only about 3 years old so I wonder if.it was just a bit of a bad paint job!

 

[Cubist]

Most likely its the product of poor preparation of the surfaces to be painted and maybe the use of less expensive pre-paint treatments and paints themselves.

 

[Stevers]

Thank you! In this case is there much I can do apart from caulking?

Assuming everything is fastened properly, then it's just down to what you caulk with. Perhaps this is the time to break out one of those modified polymer sealants/adhesives like CT1 which retain a bit of flexibility, come in lots of colours and stick really well.

As it's a bay window make sure the roof is sound too - any leadwork and internal gutters in particular. A picture of the outside might help us highlight potential faults.

 

[Mr_Green]

The external cill isn't allowing the rain to run off, so it's soaking in down the sides and into the wall. I had the same, took all the plaster off, sealed around the frame and patched up. Good as new.

 

[RVP]

thanks so much for your help all! I think I'm still a bit lost as to where needs re-caulking as I currently can't see where that would go - photos attached. Would it be just along the bottom of the wooden white bit?

 

[Stevers]

A picture of the outside might help us highlight potential faults.

Generally, water travels down and across, so at least initially, you need to aim a lot higher, and show at least the whole bay, if not the whole front.

The amount of water coming in suggests that something is fairly seriously amiss further up.

 

[Cubist]

I concur with Stevers. You need to look up to examine the top edge of the frame and the vertical sides where they meet the brick/stone work.

 

[RVP]

Thanks for your help! I've taken a look at the top of the windows and can't see a reason they'd be leaking from above. I'm pretty sure it's water on the windowsill leaking in, have attached photos

 

[Cubist]

Looking again at the earlier photos and these latest I can see what may be the root of the problem. The window frames and the outer stone facade seem to have been freshly painted and the wooden inner frame looks to have been poorly prepared. You need to look closely at the seams where the stone meets to the woodwork as this is where any caulking material would usually be installed. While doing so you need to be aware that the wooden frame under the paint will move - expand and contract - with changes of weather conditions and also, to some extent the interior heating systems. An effective caulking material will usually cope with this movement but if it were damaged, say during preparation for painting, or simply aged and decayed, fine cracks can open up to allow ingress of driven rainwater. Similarly, there is a gap between the bottom edge of the inner sash that could also be an ingress route for driven rain; opening the sash after a heavy rain might provide evidence to confirm/reject this possibility and also to establish whether the weather shields are in place and effective.

On balance I suspect that the original caulking is old and was not refreshed during the preparations for painting the exterior and in my view you should consider rooting all of it out and installing a new and suitable flexible caulking sealant around all the seams between the stone faced and the inner wooden frame. This is a daily simple job but best done during periods of dry weather so perhaps best left now to maybe next spring. You could, however, apply a temporary fix that will tide you over the winter months, and confirm that this is truly the problem, by slightly opening the seam line and firmly pressing some plumbers putty into the gap. The putty will adhere to both the stone and the wooden frame to form an impermeable barrier to halt water ingress. Plumbers putty never sets and is easy to remove later while glazers putty does set and can become difficult to shift.

 

[Stevers]

Thank you Cubist! I had never considered using 'Plumbers Mate' or equivalent for this sort of thing, but will now be using it as a removable sealant on elements of my current garage door and door frame repair.

It would be interesting to know if it's just you, or if neighbours upstairs or residents elsewhere in the building have the same problem.

 

[Cubist]

Thank you Cubist! I had never considered using 'Plumbers Mate' or equivalent for this sort of thing, but will now be using it as a removable sealant on elements of my current garage door and door frame repair.

It would be interesting to know if it's just you, or if neighbours upstairs or residents elsewhere in the building have the same problem.

My pleasure, Though I was not too happy when I discovered the technique. A PO here had used it to caulk some of the exterior render panels here UNDER an additional seam of silicon!??

However, disposable gloves, a small spatular/pallete knife or similar and a small amount of linseed oil are good to have around when using - its horribly sticky and ends up everywhere.

 

[RVP]

Thanks so much for all the advice! I'm waiting for a break in the rain to try out the plumbers putty, I will report back!

 

[Cubist]

Eh wot? Plumbers putty is waterproof! Get a hat and get on with it. Immediate results and dry interior being lost to a little drizzle shocking, absolutely shocking.

 

[Persis]

Your windows may be leaky but they are really pretty!!