What type of wall is this? Age of house?

[David]

I wouldn't, judging on the ones I have been in, I was just interesting on how older houses compare to newer modern ones.

[John Williamson]

That's the problem. The place I'm looking at needs redecorating anyway, and the insulation job involves applying a fairly thick insulating plasterboard to the interior. Materials and extra labour add up to about the figure I mentioned, *over and above* the normal costs.

External insulation is more expensive, and may need approval of some sort.

[John Williamson]

Not ideal, that. Obviously, you need insulation above your ceiling, and the stuff below the floor taken out. But I'm sure you'd worked that out already.....

[Dave Liquorice]

yes there will be upheaval and newly decorated doesn't help. However the savings may well be be considerable 9" solid brick walls leak heat rather badly compared to 50mm of celotex/kingspan insulation board over 9" solid brick walls.

Have a play with some of the online heat loss calculators. you can probably cut the heat loss, and thus the space heating energy bill, by a good 50% by adding insulation.

pretty good and allows you to enter U values for walls rather than limited selection of types. Be aware that the default external temp is 8C, it's more usual to use something nearer 0C...

[David]

m

f

Ah I see what you mean.

[David]

Indeed, the person who done the roof and the loft conversion wasn't exactly professional unfortunately as we found out later! I believe if the loft is going to be used the insulation should be a 'warm roof' type.

[David]

That seems very good, I am going to make some measurements and see what the calculator comes up with. If we were to put 50mm celotex over the walls, would we need a DPM too?

[Tabby]

It does cost to insulate, but they can get their money back and more. External insulation is a fair bit more cost. I'd start by drilling a little hole 6mm in the wall to see if its a cavity type - if it is, you're in luck. Cavity wall insulation is much cheaper than other methods, and lkeeps some of the blockworks inside the insulation, improving thermal performance.

NT

[Tabby]

yet another poorly consutructed surevy

NT

[Hugo Nebula]

Not unless you're going to remove all the existing tiles and raise the ridgeline by up to 100mm. A "warm roof" is where the insulation is wholly or partially above the rafters. Anything else is a cold roof, and don't let the manufacturers of breathable membranes or magical multi-foil insulation sprinkled with pixie dust tell you otherwise. If they do, they are charlatans who don't understand what they're selling (or are trying to mislead).

[The Natural Philosopher]

No.

A warm roof is simply one with a without a cold ventilated loft space.

Typically the insulation is between the rafters with an air gap above,

[Rick Hughes]

Lath & plaster wall as others have pointed out - non load bearing. Impossible to age from the photo

[Andrew Gabriel]

Yes, it's header-stretcher-header-stretcher-header-stretcher..., i.e. a Flemish bond 9" wall.

[newshound]

Mine too

[John Rumm]

The phrase "Warm deck" or "warm roof" does have a specific meaning in the building regs - it applies when the roof structural timbers are inside the thermal envelope created by the insulation, and hence there is no possibility of interstitial condensation causing them to rot.

That's a cold roof or cold deck. Commonly done for loft conversions, and at one time common for flat roofs - although less so now.

[John Rumm]

Probably (almost certainly in this case) non load bearing - just worth keeping in mind that contrary to popular belief, stud walls can be load bearing.

[The Natural Philosopher]

Not where my BCO was concerned.

[Hugo Nebula]

No?

That's a COLD ROOF!

Any type of roof where some or all of the supporting timber is at or below the dew point is a Cold Roof.

[Hugo Nebula]

Not necessarily. I've seen snapped headers used with cavity walls; presumably to give the impression of solid 9" walls rather than 4" walls.

[Hugo Nebula]

Your BCO wants to read his BS 5250 then.