IWI and window frames

[Maria D]

I’ve been reading a lot of threads here about breathable internal
wall insulation and would like to do some as part of my renovation of a 1915 Edwardian house. As I don’t want to rip out coving etc downstairs, I think it might only be an option for the bedrooms on the 1st Floor. My query is how to work around original decorative window surrounds? Any advice appreciated.

 

[aockenden]

Can we please see more pics from further away and straight-on?

 

[fernicarry]

What's the external wall construction? If you are building up extra wall depth then ideally you should move all of the decorative joinery inwards to compensate but it will be quite hit and miss whether or not you can get it off sufficiently undamaged to reuse.

The window reveal itself will be the worst performing thermal-wise. The cappings inside the opening don't look terribly decorative, but they might be hiding something far nicer underneath. I'd get those off for starters to see what you are dealing with. If there is a void between the window paneling and the external masonry you can remove the window board and fill with something like this.

 

[Stevers]

I reckon you're missing a set of folding shutters and a boxed sash window. It's possible though it's not impossible that there's still original panelling beneath the window under all that Plasterboard.

My thing though is originality (and pullovers) rather than insulation (and comfort).

 

[Maria D]

Thanks for your replies. I’m posting another couple of photos. One is the same window and another is a downstairs living room. Aluminium windows put in in the late 1980s. My understanding is that the original windows were casement (have some still in the shed). Do you think the walls are plasterboard? I was working under the assumption that they were lime plaster, I’ve had a traditional plasterer around to look at them.

 

[fernicarry]

Aluminum window frames must be quite the condensation magnet...

Do you think the walls are plasterboard

I think @Stevers was referring to the flat panels under and alongside the upstairs window. Whatever they are made of they look suspiciously nailed or screwed on so you might, just might, find original decorative paneling under there like you have downstairs. Of course its quite likely that there is a good reason for them having been covered up...

If the window paneling is no good that works in your favour so far as insulation is concerned because you can rip it off and bang something into the window reveal to make it a bit more airtight and insulated then reinstate with something a bit nicer.

Whats the wall construction? Brick or stone? Do you know if there is a void behind the plaster? (Take an electrical socket off if you feel comfortable doing so and have a look behind it.).

 

[Stevers]

My understanding is that the original windows were casement

In 1915 they could well have been casements, though the proportions look more sash like. The stained glass is probably modern as I don't think it would have fitted in the original casements, unless they were Crittal windows rather than wood.

It doesn't look like there were shutters downstairs. However the very laid back splays upstairs look like those we have for shutters, but would they have fitted them upstairs and not downstairs? Our shutters are downstairs, and only at the front.

 

[Maria D]

You’re right, the stained glass panels were reproductions made in the made 80s and put into aluminium
windows. There are some
original glass panes and sections of windows in the shed. I wonder why the originals were replaced by casement windows if they were sash but then such an effort was made to reproduce the stained glass panes. Although the original panes that are left are too small to fit these windows. Here is one of the original panes.

 

[Maria D]

On your advice we removed the panels and found this. Wooden frame with bricks behind it.

 

[fernicarry]

Interesting arrangement with the cast iron rad...

Are you going to take off the higher up piece of hardboard too? I'm wondering why there is such a substantial piece of studwork going up behind it.

Whats your plan for IWI on the walls?

 

[Maria D]

Well take it all off and see what is hiding behind it. Two of the three bedroom have this sort of panelling while the other has similar yo the sitting room.
We were thinking of a woodfibre board system although we’re being cautious due to mixed opinions on the whether IWI is a good idea at all. Amazingly, any engineer I’ve had around don’t seem to understand the complexities of using it in older properties. One thing I’ve spotted on another thread about woodfibre is that you can’t (or at least it’s difficult) to attach anything to it such as a curtain pole. Do you know anything about this? Would you recommend we go down the road on IWI at all? We are getting the underfloor of the ground floor insulated.

 

[a twig]

Peering at the photo on my phone screen I wonder if it could have been wood panelling once upon a time. Certainly looks like it might have been stained or had some sort of finish applied in the past.

When doing the wood fibre, work out where you want the mounts for the curtain poles to go and cut out the insulation and mount wooden blocks to the wall (with a small bit of DPC roll between the block and the wall for good measure) then your curtain rail mounts screw into those

 

[fernicarry]

Well, improving the thermal performance of older buildings is pretty much a no-brainer for me. Energy prices are only going one way and govt policy is making it progressively harder to take no notice and carry on as you always have. Scotland has already banned combustion heating on new builds so its only a matter of time before heat pumps become the only game in town and for those to work out you need to make the building perform an awful lot better than it has done.

Objections to WI tend to be more on aesthetic grounds, your choices being either destroy the original features inside the building or cover up those on the outside. Neither being particularly acceptable IMO but I keep chipping away at what I can in the hope that when the time comes I can still flog this place to a like minded individual without having to take too much of a hair cut.

 

[paulc]

Scotland has already banned combustion heating on new builds so its only a matter of time before heat pumps become the only game in town and for those to work out you need to make the building perform an awful lot better than it has done.

Improving the thermal performance of a building will ensure the heating system performs better and reduce running costs. The source of heat makes no difference in that respect. Even in a draughty, poorly insulated property, if a heat pump is appropriately specified and set up, running costs should be on par with gas, and on the right tariff, perhaps even cheaper.

 

[fernicarry]

running costs should be on par with gas

This place needs a flow temp of 65' or more in the winter and we already have the largest radiators I can squeeze in. A HP isn't going to hit the COP needed to make running costs comparable with gas under my current conditions. And that's ignoring the very substantial capital outlay of installing one.

The price of gas and electricity needs to diverge a lot more before it becomes viable for me. Preferably by electricity prices dropping to the levels we've been promised that renewables will deliver so that its not just about same running cost as gas but a whole lot cheaper. That might motivate me to make the transition.

Realistically that's not going to happen. There are still many years, decades more like, of investment needed to strengthen the entire electricity system to the point that we can turn off fossils so that will continue to weigh bills down. Whats more likely is that the cost of gas will continue to ratchet up especially with the whole geopolitical situation worsening. So on that basis, I agree, any improvement in thermal performance is essential for hedging against even increasing prices.

Even so I can still buy an awful lot of gas for the price of a HP, or for the price of double glazed windows throughout, or for the cost of ripping out the inside of the house and going full IWI. And if I choose not to do those things then I expect their cost will be priced into the value of the property when next it comes on the market.

Maybe I'm an outlier but I think there is a substantial minority of buildings in the same situation.

 

[a twig]

I took a similar view at our last place, a lot of the measures would have been unlikely to have paid back in anything under 20 years and I was more concerned about ventilation, breathability and preserving the building.

Didn’t impact our final sale price particularly when we ended up having to sell.