Wall insulation for PPOR renovation

Bought ourselves a 1930s home in need of tlc as a ppor. Now that we have stopped it falling down (restumping), burning down (rewiring) or flooding ( roof repaired, new drains, water pipes repaired) its time to look at painting.

Many of the boards are rotted at the corners which got me to thinking should I remove them all and insulate the walls? Is the comfort and energy cost differential sufficient to offset installation costs? I have yet to insulate roof or floor but these are inexpensive diy jobs.

We will be doing a rear extension in 12-18 months, but in the mean time Id like to get the front up to scratch, and while i have some oth boards removed....

Cheers,
Scott

 

If the boards are off, insulate!

But read about it first so it is done correctly and you don't get water wicking through to your plasterboard or condensation causing your studs to rot...etc

 

If you're taking off the boards anyway, you could insulate from the outside.
I would be looking at replacing the gyprock to the outward facing walls on the inside if it needed it, and putting insulation in there.

 

Perhaps I was a little unclear....rather than how to do it I was looking for experiences of whether or not its worth the effort.

As I walk around the house the bottom 8-10 weatherboards are rotted at the corners. Easiest option is just to replace the ends (staggered joins over first 1 to 2 studs). Gyprock inside is in good nick and is actually stucco horsehair so will only be getting a wash and paint.

So the real question is "return on investment". While there is a benefit to insulating the walls, does it justify stripping all the external cladding to do it?

Will be insulating ceiling before summer, and most likely floors too as floors are cheap and easy. Clearly insulating walls completes the package....but does the benefit justify the cost/effort????

 

I have done this on my PPOR - because it was so cold and there was almost no room to increase the ceiling insulation. Also the plasterboard was in bad condition.

However, retrofitting is a pita, destructive and costly if you don't need to expose the walls anyway and aren't DIYing.

The wall insulation has made a difference in my house. But if I had a ceiling space, I wouldn't have bothered.

I recommend just sealing gaps around windows, doors etc, and use thick curtains and outside awnings, or other shade, for a similar effect to wall insulation.

 

It is undoubtedly worth doing and a complete no brainer. Id rather a well insulated house and an older say bathroom or kitchen appliances or whatever if the budgey didnt allow.

Up to 35% of heat loss and gain is through walls. 35%. Assuming you arent changing windows, which in an old home are usuallu horribly inefficient, this makes the importance of wall, floor(if raised) and roof and ceiling insulation even more important.

Do it and do it properly, not just the minimum imo.

 

Imo they arent mutually exclusive, yes each will make a difference and depending on orientation, shade, roof materials etc doing ceiling insilation i/o wall might be oknif you could only do 1 option but there is simply no escaping the fact that just about every single calc or diagram ive seen shows heat loss or gain through walls to be around 30% of the entire house. Thats far too vast a figure to be ignored. Ceiling is often the easiest one to fix which is why its done but in this case during renos etc id really consider it to be a no brainer.

 

I wouldnt unless you had to have all the weatherboards ripped off anyway.

I replaced weatherboards on one side and insulated that wall. Made no difference.

You got to remember our old houses have old windows and doors that dont seal well anyway. So its a bit of a lost cause.

With that said I will try insulating my roof as its a tin roof and I think that would make s difference.

 

You insulated 1 wall. Of course it wouldnt make a difference...

 

I would have thought insulating the whole north facing wall that had sun hitting it all day would have taken some edge off the heat.

 

I have a Nth 'fencing ' wall' which blew in the wind, I had it wool insulated and gyprocked, it holds the warmth in now.

 

That would help with radiant heat gain but does zero for convection heat gain affecting the rest of the house which is why the house would have got hot anyway.

Btw this is in no way an opinion based on nothing, its basic but thoroughly verifiable anf widely tested info.

 

Ceilings and roof spaces account for 25–35% of winter heat loss and must be well insulated. To prevent heat loss, place most of the insulation next to the ceiling as this is where the greatest temperature control is required.



Principles of good insulation.

Floors account for 10–20% of winter heat loss. In cool climates insulate the underside of suspended timber floors and suspended concrete slabs. Insulate the edges of ground slabs. Insulation is not required beneath earth-coupled concrete slabs; however, installation may be desirable when groundwater is present (see Insulation installation). Waffle pod construction helps to insulate under slabs.

Walls account for 15–25% of winter heat loss. Insulation levels in walls are often limited by cavity or frame width. In cold climates, alternative wall construction systems that allow higher insulation levels are recommended (see Lightweight framing).

Source: your home.gov.au (28 August 2016)

 

Completrly agree with the above, it also proves my point that while ceiling insulation is the easiest and the best bang for buck youre still only targeting 35% and ignoring 65%-75%

 

Im a fan of insulation , for noise reduction also. Sarking is great as well.
I brought home a FLIR camera from work and walked around our house one winters evening. I was blown away by the heat loss due to no wall insulation. I could clearly see the heat transferred by each nail holding on the weatherboards.