Solid Wall Insulation - Limited Space

[MontyMonty]

We live in a 1920s three bed end of terrace. Walls are solid. The hall gets very cold in the winter. We made things worse when we stripped the wallpaper and re-skimmed a couple of years ago. Stairs are fairly narrow as it is so we only have about 15mm to work with. We already have a big double rad. Only options I could think of are:

10mm Marmox insulation board (possibly 12.5mm) or 4mm Erfut Wallrock insulated wallpaper.

I suspect the first option will cost twice as much as the second.

I asked the same question last year. Did not end up doing anything to the wall, but did replace the front door with a composite one. Also cut out all the drafts. Wondered if there are any new products on the market that are worth considering?

Also, if I was to go with the Wallrock option, how easy is it to get off, if, after a couple of years I decide to try something else.

Grateful for any advice.

 

[freddiemercurystwin]

Lose more space or wear an extra jumper. There' ain't a magic bullet for this issue.

 

[ban-all-sheds]

External wall insulation.

 

[catlad]

Why don't you insulate the outside of the gable end if you are end of terrace.

 

[MontyMonty]

Hu,

I assumed, perhaps wrongly, that external insulation would be quite pricey.
Unfortunately our budget it limited.

Any idea of the cost? Average 3 bed end of terrace in S E London.

Thanks

 

[nebjamin]

An informed guess: 15k

 

[ban-all-sheds]

I assumed, perhaps wrongly, that external insulation would be quite pricey.

That would not be an incorrect assumption.

 

[jabuzzard]

One option would be to hack the plaster off the wall before finishing the wall with insulated plasterboard and skimming. You could easily get another 10-15mm of depth.

Something else to consider if you have not already done so is insulating the floor. A 1920's house is likely to have a suspended timber floor. You may also have a bit of the bottom of the stairs which is open to the underfloor area, and is effectively "outside" and can also benefit from insulation.

 

[MontyMonty]

Thank you all for your comments.

Jabuzzard - I have considered hacking off the old plaster. What puts me off is the size of the wall and the almighty mess it would make. Plus the fact that the plaster in our house is rock hard. Don't know what they put in their plaster in those days but it is certainly solid.

I am now reconsidering having to lose some of the space on the stairs.

I know it is hard to guage but what do people think is the minimum thickness insulation I could use that would make a noticeable difference to the temperature in the hall. 25mm? And would Marmox board be a sensible choice? What are the alternatives? Thanks.

 

[jabuzzard]

Obviously the more insulation the better. Probably the first question is how long do you expect to stay at the current property? Clearly the longer you stay the more value you will gain from the work.

All the main manufactures do plasterboard that is bonded to varying thicknesses of CFC-extruded polystyrene. They start at 27mm thick and move upwards. Work out how much space you are prepared to loose and then fit the thickest insulation you can. Note that an SDS drill with rotary stop and a wide tile removing chisel you should be able to shift the plaster from the wall in a day.

One point to bear in mind that you might not save any money once you are finished. If the heating going full crank leaves the room cold, then you could find you end up with the hearing going full crank and getting the room to an acceptable temperature.

Personally I would start if you have not done so already by draught proofing, and insulating the floor, paying attention to the bottom few steps of the stairs. In my house for example these are open to the underfloor space and are not insulated. They are measurably colder than further up. I have not yet devised a scheme for insulating them however.

 

[MontyMonty]

Thanks for your advice Jabuzzard. It' svery helpful.

I will certainly look at the area under the stairs to see if I can insulate it better.

Definitely going to go with 25-30 mm of insulation on the wall. Will also consider hacking off the old plaster.

Can anyone advise on the best insulated plasterboard to use? Or are they all pretty much the same?

Thanks