Heat efficiency.

[Emjay86]

Hey guys,

Im curious as to how you are all keeping the house warm in winter and cold in summer.

I appreciate that this question may come across a bit obvious what with central heating for the winter and typically opening a window for the summer but what other methods are you all using to aid in these times?

During the lovely two weeks of hot weather we have had its been over 32 degrees C in our house and I simply cannot get the heat out. Then it gets to winter and we have to have the heating on almost all the time. We have insulation in the attic (just a small amount of fibre glass, about 4-6 inches of the stuff) but some of it is being covered by some boards I put down so we could use it as storage. Does this affect the efficiency of the insulation?

Cheers!

 

[Emjay86]

The joy of old houses. Freezing in winter but nice and cool in summer.

Sounds great but this house is a new build and its just over 1 and a half years old.

Figure that one out

I just read that over again and I think I got it wrong the first time!

Oh well you get the idea.

 

[Emjay86]

If you look at buildings in hot countries they are often designed to make use of the chimney effect, hot air rises and creates a convection current drawing in cooler air.
Basically open the back door, the stair door and then all the windows in one bedroom, air should flow up and out of the house.
Meanwhile keep all the curtains closed to reduce solar heating.

I'm in an old house (well, 70's) and it's as cool as a Spring day, but sub Arctic in Winter.

Ill definately try this thanks!

 

[Emjay86]

It seems strange that you have such a small amount of insulation in a new build, and if the boards are squashing it then you'll definitely be reducing it's effectiveness.

As for summer cooling, then the chimney effect described above works well for us. We can't really be leaving windows and doors open during the day when we're out but we have blackout blinds closed on the south side of the house.

It's a pity we can't store all of the excess heat for use in the winter!!

Yea your right.

Ill have to look into getting more/better insulation for the house. Think the first on the list is the wall cavity stuff. Heard its good and apparantly there is a grant of some sorts from the government for it.

Not sure what else I can do though. Ive seen those foam boards being used before perhaps they are better then a bunch of fibreglass?

 

[Emjay86]

Also is there a particular way the fibreglass should be laid? Because theres a load of it down that looks like its been put in properly and then theres a load just thrown all over the place.

 

[Emjay86]

I don't know about Wales but I'm pretty sure all new builds in England have cavity walls insulated as standard, plus I think the recommended insulation in the loft is 270mm for fiberglass. I'd be checking with the builder to make sure they've built your house to the required specs!

As a rule loft insulation is laid in between and up to the top of the joists, then cross laid at right angles over the top of the joists to make up the required thickness.

From what your saying it sounds like they havn't done a proper job which isnt hugely surprising.

I have the fibreglass between the joists and then whatever was left seems to have been tossed over anything. In some parts you can see the joists and in others theres a mountain of fibreglass. Its literally just been thrown in.

As for the actual roof. Beyond the angled joists holding the roof up there is nothing. There is a thin black sheet of sorts and then it goes straight onto tiles. Im pretty sure that something else should be there?

As I said I wouldn't be hugely surprised. My french doors at the back of the property had around 75% of the screws missing, my front door wasn't correctly sealed and the threshold wasn't screwed down so bugs and all sorts were crawling through during winter. My windows were incorrectly lined up and the child safety things were completely off on some of them. My bath was incorrectly sealed as they hadn't filled the bath with water prior to sealing thus once used it just dropped away from the seal. Plenty of stuff gone wrong!

 

[Emjay86]

You have a cold roof so no need for anything under the tiles it's pointless.

Modern stuff often conflicts in building regulations to comfort ie we build 140mm insulation in walls and floors then 400mm in lofts then have to cut the air loss to almost zero if that's in a timber frame building with pretty much no thermal mass then it'll just get stuffy.

If you have a brick and block house then cool it down at night then it'll absorb the heat during the day.

Cross flow of air
Open your loft hatch
Close curtains

If I go into the loft right now its baking. Its well over 35 degrees up there. Would that be normal?

 

[Emjay86]

Yep its from solar gain, the sun heats up the attic space from radiant energy, you can prevent this by fitting a radiant barrier and ventilation.

I have heard of this.

Do you know how much it would roughly cost for a small house (2 bedroom) and who id need to hire to get it done proffessionaly?

Cheers!

 

[Emjay86]

You should have a decent amount of cross ventilation in a cold roof which will prevent it getting hot although before they were insulated the soffits and eaves were pretty much sealed, if you have loft insulation fitted you should have extra vents fitted to the eaves. We had circular vents drilled in but when we had them overclad we fitted the linear vent now it's nice and cool and we crack the hatch open if it's hot

What will these vents look like?

It doesn't look like I have any vents. Im very curious as to how good a job they have done frankly.

One of my neighbours house's roof was made using half-rotted wood and odd cut-offs. Clearly a way to save money but it was a botch job as you can gather. Luckily they knew it was off when they first saw it and got it fixed.

So I do tend to try and fine comb everything. Bunch of cowboys building these new housing developments tbh.