Victorian Bay Window

[Stevieb12345]

Morning.

 

I'm going to be looking at insulating behind the wood panelling in my living room. When you look down the gaps it has a large gap below the three windows and two very large voids on both ends panels. Lots of drafts and noise can be heard.  I think it's original and not keen on removing it to do the job if possible. 

 

What would be the best way forward?

[Redbeard]

Remove it, insulate behind and re-fit with amended joinery details as required. It's what we did. (Mainly 40mm wood-fibre, and 100mm wood-fibre on the flanks each side of the bay)

[Sparrowhawk]

22 hours ago, Stevieb12345 said:

Morning.

 

I'm going to be looking at insulating behind the wood panelling in my living room. When you look down the gaps it has a large gap below the three windows and two very large voids on both ends panels. Lots of drafts and noise can be heard.  I think it's original and not keen on removing it to do the job if possible. 

 

What would be the best way forward?

 

Hi @Stevieb12345 and welcome to the forum.

 

You could drill holes in the panelling, fill with expanding foam and hope for the best - I have seen people do this.

 

But given the risks that brings, what you've said about drafts and noise, what I can make out of the standard of window fitting, plus what I've found stripping back my 1920s wooden window surrounds, I agree with Redbeard. You're going to be surprised - and shocked - by what you find behind there.

 

Yes it's a bigger job and disruptive to your living room but it will be worth it once done for improved comfort. A bonus is it'll let you strip the paint from the wood - including the layers of lead paint - somewhere that's not in your living room. Or send them away for stripping. Or (and this is my preference, which I'm doing here) replace with new 'clean' wood. Which also lets you adjust the dimensions to add a thicker layer of insulation behind it.

[IGP]

If it was me, I’d do it properly by removing the wood and sorting whatever you find.

 

If you can restore it, great. If not, do something in keeping with it. 
 

Be comfortable in your home! 

[Stevieb12345]

Thanks, everyone.

 

My initial thoughts were to remove it, but other people had started to talk me out of it. It's a big cold house so it needs sorting properly.

 

Do I need to make a frame to hold the insulation? And what's the best one to use?

[IGP]

The draughtproofing / Airtightness is the priority as that’s where most of the heat is lost and noise comes from. Repair any brickwork, fill all gaps - I’ve used Illbruck FM330 airtight expanding foam from recommendations on here and it’s amazing. 
 

The insulation then deals with the conduction of heat through the fabric. I think the usual method and the one we did was to build a wooden frame / battens and put foil backed PIR in and foam it around to just to secure it and minimise gaps, then aluminium tape everywhere that isn’t foiled (the wood, the gaps between the wood and the PIR insulation). The foil / aluminium tape stop the vapour, crossing the insulation to the now much colder wall and condensing and causing mould / rotting stuff behind there so it’s important to get this vapour barrier detailed right, thankfully it’s not difficult. 

[Sparrowhawk]

56 minutes ago, Stevieb12345 said:

Do I need to make a frame to hold the insulation? And what's the best one to use?

 

Strip it off and post photos on here before making a final decision on what to do. What insulation to use is going to depend on a lot of factors, like if there's a cavity, wall construction, any signs of damp etc. That's where vapour permeable insulation like @Redbeard's wood fibre insulation, vs @IGP's vapour impermeable insulation with a vapour control layer (VCL) is an important choice.

[Stevieb12345]

Of the five panels, four came off quite easily; however, where they touch the floorboards at the bottom, they are rotten. I cleared a good deal of debris out from behind them. There are certain areas where the pointing is in bad shape and you can see daylight.

Edited July 15 by Stevieb12345

[Redbeard]

Ours was 112mm brick, with stone details, but dry. We did lime parge coat then 40mm rigid wood-fibre, plastered and primed/air-tightness-taped, then rough-coat plastered, then replaced panelling, amended as necessary.

[IGP]

Can’t quite tell, but the pictures look like there are was some fairly sizeable gaps between the floorboards and the wall. If that’s the case I can imagine lots of cold air being blown up on a breezy day. Possibly a major contributor to rotting the bottom of the woodwork if warm vapour is condensing on the cold wood.

 

[Stevieb12345]

21 hours ago, Redbeard said:

Ours was 112mm brick, with stone details, but dry. We did lime parge coat then 40mm rigid wood-fibre, plastered and primed/air-tightness-taped, then rough-coat plastered, then replaced panelling, amended as necessary.

Would that fill all the holes and gaps? Or is it just a thin layer?

 

 

[Stevieb12345]

1 hour ago, IGP said:

Can’t quite tell, but the pictures look like there are was some fairly sizeable gaps between the floorboards and the wall. If that’s the case I can imagine lots of cold air being blown up on a breezy day. Possibly a major contributor to rotting the bottom of the woodwork if warm vapour is condensing on the cold wood.

 

The floorboards are also rotten along the edges of where the panelling has been sitting on them, as are the ends of the joists. 
 

The jobs just get bigger and bigger.

Edited July 16 by Stevieb12345

[Sparrowhawk]

9 minutes ago, Stevieb12345 said:

The jobs just get bigger and bigger.

We knows that feeling

 

While there, have you considered adding under-floor airtightness and insulation? /ducks

[IGP]

I’ll just leave this here. 
 

https://www.ecologicalbuildingsystems.com/post/best-practice-approach-insulating-suspended-timber-floors

[Stevieb12345]

On 17/07/2024 at 16:49, IGP said:

I’ll just leave this here. 
 

https://www.ecologicalbuildingsystems.com/post/best-practice-approach-insulating-suspended-timber-floors

Thanks. 
 

I’m going to use the PIR boards once the damp and other things are sorted. The drafts are unreal when it’s windy. The boiler, pipework and radiators are all brand new and over spec but struggle.

 

 

[IGP]

Making my ground floor windproof & insulated (as much as realistically possible in retrofit) has made the world of difference. Along with MVHR has been one of the best investments I’ve made. 

[Stevieb12345]

A bit of progress on the bay window. All the gaps have been filled in and built out. You can notice less sound from the outside too. Next stage in the membrane.

[scottishjohn]

I might have been tempted to bring the walls into get serious insulation+water proofing and make it into a window seat 

 

Edited August 18 by scottishjohn

[marshian]

On 20/07/2024 at 10:55, IGP said:

Making my ground floor windproof & insulated (as much as realistically possible in retrofit) has made the world of difference. Along with MVHR has been one of the best investments I’ve made. 

A couple of years ago it took me several months of every weekend to do the insulation retrofit install on my suspended ground floor. Working from the crawl space under the house (I had finished floors in most of the rooms that I was reluctant to rip up, ceramic tiled and oak boarding) but I have absolutely no regrets.

 

It has had a bigger individual impact on energy reduction than double glazed windows, cavity wall or loft insulation did.

 

I only wish I'd done it 33 years ago when we moved in to the house - I was younger, fitter and it would have hurt less!!!

[Stevieb12345]

I’ve been working on the bay window when I can and it’s almost done. I just need to fill the gaps and paint it a few times to get the paint thickness the same as the rest of the room.

 

The floor is coming up on the 15th so I can insulate it.

[Sparrowhawk]

Looks great! You mentioned less sound coming in before; anything else you're noticing now the woodwork's back on?