Decorative Coving - remove or not?

[Maria D]

Hi Everyone,
As I've mentioned in other posts, we are planning on internally insulating the exterior walls of our new detached Edwardian redbrick with woodfibre boards and plastering with lime plaster. The house has 3 floors and our initial plan was just to insulate the top two floors as there are fewer original features to mess with in these rooms. The supplier has recommended we insulate the two reception rooms on the ground floor. I know this makes sense, but including these rooms in the insulating plan will mean taking our the beautiful decorative original coving that has been in place for more than 115 years. We could probably get a company to replicate the orginial, but I hate the idea of ripping out features that have been in pace for so long and are th ereason I bought the hous ein the first place. I'd appreciate opinions on this. Could we get away with a layer on insulating plaster in these walls instead? The existing lime plaster on these walls is in decent condition. Am I wasting my time (from the heat retention viewpoint) insulating the upper floors but not the lower one? The kitchen is a more modern extension and is insulated already. Old houses throw up so many issues! Many thanks.

 

[Gothichome]

It’s a hard decision, it really all depends on your commitment to maintaining the home. I would suggest the cost of bringing in a plasterer to replaster and make new coving will way outweigh the savings gained by insulating. But that’s just my view.

 

[Maria D]

That’s a good point. There’s a degree of Cost Benefit Analysis that is worth doing. I guess I’m wondering if it a an “All or Nothing” situation when it comes to insulating the internal walls.

 

[fernicarry]

Insulating plaster is better than nothing but most products are about half as effective as wood fibre and its ilk. Diathonite nearly matches but has a significant price premium iirc. You'll generally be putting insulating plaster on in a much thinner layer than solid insulation so that compounds the lack of performance.

If you hack off the existing plaster but keep the cornice how much depth would you have? Factor in the depth of your finish coats and do a before and after heat loss calculation to work out what you would gain. You'll get the most benefit from the rooms you normally occupy. Rooms used solely as bedrooms aren't worth it IMO as they don't need to be heated to as high a temperature or for as long as say the living room. You might be using your upstairs rooms for other purposes however that would justify improving them.

I'm in a similar situation. Loath to sacrifice original fabric unless its really knackered. But also have to keep an eye on ever increasing running costs and the possibility of resale value taking a hit without meaningful improvements.

 

[Cubist]

The supplier has recommended we insulate the two reception rooms on the ground floor. I know this makes sense,

I wouldn't be so sure that it makes sense. Assuming your house follows the typical Edwardian patterns in terms of layout then it's likely that the reception rooms you are concerned about each have only two external walls and at worst three. No doubt these rooms will also include large window areas, perhaps enclosed in bays, and probably a large fireplace/chimney breast. These features alone will seriously reduce the available wall surface area via which savings resulting from the addition of insulation could reasonably be accrued. Other germane considerations that come to mind include your normal heating habits for these rooms and, perhaps more importantly, whether the interior doors are left open to allow warmer air produced on the ground floor to transfer to the upper floors via the hall and stairwell.

I think in your shoes I would also look again at the upper floors too as these may share similar characteristics to the reception rooms in terms of windows and fireplace/chimney breasts. It could be that the Cost v Benefit and Payback arguments just don't work at all.

 

[CliffordPope]

Living in a period house means exactly that. It doesn't mean viewing it on a hot summer's day, then discovering it's bloody cold in winter with a gale blowing through, so pulling out all the period features and insulating like mad. That's just re-creating the modern house perhaps you should have bought.

So we compromise a bit, buy more wooly jumpers, and retreat to the warmest part in winter and stoke up the fire.
Life is seasonal - just more difficult as we get older!

 

[Maria D]

I’ve had quite a lot of trades people advise me to rip everything out, but as you say, I wouldn’t have bought a period home to then make it like the newer home I’m leaving!
Cubist, you’re right, the reception rooms both have one wall made up mostly of windows (and in fact we one external wall that has a doorway to the outside also!) and both have open fires. We will be putting in stoves, but I’m really not sure insulating these rooms will give us much additional heat. I’ll do the figures and go from there. Thanks for all the advice, it’s very helpful.

 

[fernicarry]

stoke up the fire

Back in the day this house would have had live-in staff who kept the fires stoked and the coal was dug out of the ground a few miles away and brought to us by puffer, later by rail. With the best will in the world we can't live in these houses in the same way as when first built.

I don't advocate pulling out original features either but with the direction of travel on energy cost and policy I don't see these buildings lasting another generation without some degree of improvement to their thermal performance.

doorway to the outside also

The first thing to address is air tightness. No point in adding insulation if the wind is howling around it. Get the windows and external facing door properly draft proofed as well as all the gaps around the joinery filled. If you have a suspended floor think about putting a membrane below it to stop drafts between the boards. Only then start worrying about insulation. If you have a contractor doing this work they absolutely have to help you take a holistic view, they can't just come in and glue some boards on the walls and then leave you to it.

The back room I'm renovating at the moment has a door directly into the garden which previously had all the thermal and airtightness properties of a sieve. When I fitted the replacement (reclaimed, possibly older than the house) I added two layers of weather seal around the frame. The difference when you close the door is quite remarkable as the room becomes virtually silent. I figure if I can make a meaningful dent in the air tightness and add a bit of insulation then there will be less pressure to do things like rip out the 160 year old sliding sash windows and replace with plastic ones. Whether that plan survives first contact with the next owner remains to be seen...

 

[Maria D]

Great advice! We are replacing the exterior door with a picture window and having all the windows in the house replaced. We have already engaged a contractor to do the underfloor insulation, so think we’ve covered a lot of bases with regards airtightness. As said earlier, perfection can be the enemy of the good. I think if we can make as many improvements as are feasible without destroying the integrity of the house (and for a price we can afford), then at least we’ll have gone some way at to having a warmer house, albeit within the restrictions of a period property.

 

[paulc]

Cubist, you’re right, the reception rooms both have one wall made up mostly of windows (and in fact we one external wall that has a doorway to the outside also!) and both have open fires. We will be putting in stoves, but I’m really not sure insulating these rooms will give us much additional heat.

Most of your heat loss will be through the acres of glass and also up the chimney. No point in insulating the walls if they only account for a small amount of the total heat loss.
I've insulated some of the walls here, and to be honest, can't really measure any savings. But it has stopped the walls from attracting condensation and the attendant black mould.