UPVC Window - Cracking Seal/Wallpaper and Dusty Gap Behind It (Photos)

[TheGraciousNobody]

We're currently decorating my sister's flat, and this is stopping us. The Landlord won't deal with most things, so that is out of the question.

In colder months, you can notice a slight draft around the window and even noise on windy days. Dust will eventually accumulate. She had to stuff cotton wool in one bit, it was where an old TV aerial used to be.

I originally started with a blade scraper on them a little to clean them up on the right side. The paper and sealant (whatever they used) are mostly coming away. I have cut away the excess with a ruler/knife at one side. The Inner seal was doing practically nothing and would pull away in almost one piece (I didn't take photos of that.)

I hope the attached images/videos are good enough; it is difficult to see in there with the camera. (Excuse the vertical recoding - I forgot when I hit record.)

TL;DR:
How should I tackle this? They're a mess.

I assume I need to clean the area up with water/toothbrush (wallpaper and wall so it will stick down with a tube of Solvite), but what would I fill that crumbly gap up with before sticking the wallpaper back? What do I finish sealing it with? Caulk?

Thanks.

https://imgur.com/a/0ptwYBL

 

[ronniecabers]

You could probably foam the bigger gaps ( dont use a standard tin , buy a gun applicator and a gun tin ... more control on smaller places ), then when you wallpapered up to the window, run a bead of caulk round the window sealing all the gaps

 

[opps]

+1 for a proper foam gun. My Roughneck foam gun was supplied with 2 straws and two cones which taper down to 2mm. I would also recommend spending a fiver on gun cleaner.

I often leave the foam canister connected for over 6 months.

Before applying the foam, spray a mist of water into the gap. It will aid both adhesion and curing times.

Many foams will expand by a factor of upto 8, so don't go mad. A proper gun will let you dial down the flow rate.

 

[TheGraciousNobody]

Thanks for the replies.

Any particular expanding foam, caulk, gun brands/types I should get and avoid? Naturally you'd want good and long lasting results, but you don't want to overspend at the same time. The gun for example, I'll possibly almost never use it again.

 

[opps]

You can buy "minimal" expanding foam. You may be able to squeeze the straw which comes with it to make the exit as thin as possible.

Everbuild Exact Gap 750ml Expanding Foam 484702 | EVEXACT7 | Sealants and Tools Direct

Seal gaps effectively with Everbuild Exact Gap Expanding Foam, ideal for insulation and soundproofing. A precision application for all your DIY needs. Shop now!

www.sealantsandtoolsdirect.co.uk

Perhaps use tape in the event that you apply an excessive amount. Oh, and make sure that the canister is upside down. If you use it in the other orientation it releases the propellant rather than the foam. That said, after using the canister, let it release the propellant to keep the straw clean.

 

[TheGraciousNobody]

You can buy "minimal" expanding foam. You may be able to squeeze the straw which comes with it to make the exit as thin as possible.

Everbuild Exact Gap 750ml Expanding Foam 484702 | EVEXACT7 | Sealants and Tools Direct

Seal gaps effectively with Everbuild Exact Gap Expanding Foam, ideal for insulation and soundproofing. A precision application for all your DIY needs. Shop now!

www.sealantsandtoolsdirect.co.uk

Perhaps use tape in the event that you apply an excessive amount. Oh, and make sure that the canister is upside down. If you use it in the other orientation it releases the propellant rather than the foam. That said, after using the canister, let it release the propellant to keep the straw clean.

As a novice, it seems extremely difficult to find a "low-expansion" / "minimal" can... The one you linked is the only one I see that clearly states that. I assume I cannot use a gun on that. Hopefully, the built-in applicator isn't awful. Many random reviewers who review these various cans tend to say they're bad.

It is hard to tell from the pictures--There's a gap where the paper isn't really flush with anything, but also a gap where I assume air is getting through the crumbling wall, which is so small that it can hold a credit card in areas. A fair amount of dirt fell out when cutting away the seal/paper.


I need to go round the top and sides of the window. Do you think I'll encounter any issues with it falling out of the top? It also is a fair bit pricier than many other options. But again, that's the only one I see that's labelled "minimal".

Ideally I'd prefer a can with a gun application like originally mentioned ronniecabers. But my concern is that other foams could over-expansion and cause damages to surrounding materials or warping windows. I don't know how likely that actually would be though.

 

[TheGraciousNobody]

I ended up having to cut away about an inch of wallpaper. By the time I’d cleaned, filled the gap with foam, trimmed it, applied Polyfilla over the foam and the exposed area, and finally added a small bead of caulk to seal properly between the filler and the uPVC - it wasn’t perfect, but it doesn’t look too bad at all after painting.


TL;DR: Now, here’s the issue — the emulsion paint is cracking on the filler/caulk!


I was going from a darker colour to a lighter one, so I used two coats of Dulux white emulsion as a base, then two coats of my chosen colour (also Dulux emulsion). I noticed fine cracking on the second white coat - it might have been present on the first, but I didn’t spot it. It became more noticeable after the third and fourth coats. I did one coat per day, and the cracking was visible the following day each time. I think I waited about 24 hrs before painting (my memory is poor though.) I've been working on it slowly over the weeks, so I can forget where I am up to.


I’ve heard that Zinsser Peel Stop might help - apply it, wait a day, then paint over. Does this sound like a permanent solution or just a temporary shoddy fix? Would I benefit from washing or lightly sanding away as much paint as possible, or does it not matter?

Items used in order:
-Soudal Soudafoam Windows & Door Xtra Gun Grade Expanding Foam 750ml
-Ronseal Smooth Finish Filler (on the left side before running out)
-Ronseal Smooth Finish Filler Super Flexible (ordered this by mistake. )
-SX White Instantly Paintable Caulk Acrylic - Instantly Over Paintable With Water & Sythetic Based Paints - Reduces Craze Cracking -Sealing Gaps & Cracks - Interior Use
-Dulux Matt Emulsion Paint - Pure Brilliant White
-Dulux Matt Emulsion Paint - Summer Linen

Images are taken at night with flash on, so it all blends together/washed out. There's masking tape still applied to uPVC after the paint has dried (another mistake.) Edges are a bit messy. I think the white showing is paint rather the caulk. That will need tidying.

Standard filler vs flexible surely isn't the issue because it is an issue most of the way around. Some areas are clear, for now. I assume that will look terrible in several months/years if I just leave it?

 

[opps]

I have never used Peel Stop, but I do use the shellac Zinsser BIN when dealing with paint cracking on caulk.