paulr

http://homepage.ntlworld.com/paul123.../extension.jpg

Hi
I'm planning the above extension, a single storey room on the back of the house. A few people i know have done similair but the most common comment is they dont use it much as its too cold. Wanting to avoid the same problem has anyone any advice.

1. With a pitched roof is it an option to have it flat inside and lots of insulation.
2. Is it always a case of the more glass you have, the colder it is.
3. As you can see, it will be built as close as possible to next doors. Is there anything we can do, like fill the gap between the two walls with anything. ie some form of exterior insulation.

We have gas central heating and will be putting a radiator in.

Any thought, comments or just ridicule............

njkmrs

Just make sure the rad is big enough for the room .
Underfloor heating it also worth a look and feels cosy .
And as much insulation as possible .

hodgy0_2

when we extend our house with a conservatory I will put a free standing woodburning stove in

(we already have one in the main living room and they are just fanstastic)

97TURBO

http://www.orionairsales.co.uk/samsu...ter-1477-p.asp

Problem solved, cheapest heating you will ever experience and pumps it out at the flick of a switch, you wont even need insulation
Best £700 you will ever spend. Obviously the catch is finding a cheap installer if you dont know an A/C engineer.

CHOLTON

Ok I would think you would pack the roof space with insulation between the ceiling and pitch of the roof , insulate the walls with the best insulation you can afford and maybe even oversize the radiator but fit with a trv so you can regulate the temp should it get too warm , you can get skirting board especially for heating pipes to give out heat around the room . The heating pipes run through these instead or as well as a radiator . Underfloor heating is one of the most efficient ways of heating a house but it might not be enough on its own in your extension so a radiator may also be required . You can work out a rooms heat loss and find out how many btu's are required to heat it , there are websites that can help you with this .

paulr

Do you mean something like this.

http://www.youtube.com/watch?v=X6yIhyhn_eo

Isn't it all a bit messy.

hodgy0_2

yes and yes -- well sort off, it is obviously not as clean as central or under floor heating, but a good one will chuck out masses of heat, and if you use wood, can be free (and a good excuse for a walk)

they will burn coal too

nowhere near as messy as an open fire

but you are right to be concerned, I know a few people who use the conservatory as a freezer overflow facility in the winter

paulr

Any other thoughts.

Hysteria1983

The in laws have one on their boat, and its lovely!

They have this little fan that sits on top that blows the heat around. It nearly burnt my face off it gets that hot!

hodgy0_2

wear thermals

Scooby Soon!

Was going to put under floor heating on my extension but was put off by how expensive it is to run, it will be a large wood burner for me! Can't wait to have a hot house next winter

Dingdongler

Paul it's difficult to see from your pic but is the only glass the side we can see facing the garden?

How are you intending to build the walls? Insulated cavity?

paulr

Personally i'd like that to be the only glass, but that would mean a large blank wall. Not really decided.
The walls i'm open to any suggestions to improve insulation. I guess when i get an architect thats for him to sort out/ advise me.

I wont be having the glass above the doors though. I may have one roof window.
All this is in the planning stage atm.

paulr

On a practical level............

1. Do you have to relight it daily
2. Do you have a pile of logs in the living room
3. Is there any temperature control.

hodgy0_2

I have done the very same -- but gave up because the stove gives up soo much heat it isn't really needed

hodgy0_2

seriously if you can be bothered it is possible to coax it overnight so you have embers in the morning etc

but I used to ramp up the heat, so it would burn most of the night then relight it in the morning (and **** the misses afterward)

Jamz3k

Scooby Soon!

the only temperature I want is hot!

I have read in a few places that the under floor heating is 1p to run but thats normally per square metre per hour. my kitchen/diner/family room will be 40sq metre/ish which is not affordable for me to keep toasty warm.


I can get ample supplies of very good wood for nothing, my sister puts 2 or 3 decent oak logs on her fire in the winter and it lasts all night and is still going in the morning. The house is so warm and cosy, under floor heating = mildy warm which is not for me, I am sick of being cold!

hopefully something like this :

jonc

I have a similar garden room extension with a rendered exterior. It is of a timber frame construction and the a walls, pitched roof and floor is insulated with Kingspan 55mm insulation board and 48mm insulated dry lining plasterboard. It's heated with a 6ft vertical radiator rated at btu3351. All the glazing of the doors and 8 skylights are Pilkington K. The room is cold in winter mornings but once the central heating kicks in, its not too bad, about couple of degrees cooler than the rest of the house. Blinds on the skylight makes a big difference. Underfloor heating was too expensive plus our central heating uses microbore piping and electric underfloor heating is too expensive to run. We did use a small fan heater to heat the room when it was bitterly cold this winter. Hope this helps.

Hysteria1983

Agreed!

It's only really used if we are down there doing some work and the doors are open.

SpecDscooby

If its built to the same spec as your house i.e. double skins walls, insulation etc it will have EXACTLY the same thermal value as the rest of your house....therefore needs nothing more than the rest of your house to keep it warm....an extension needs nothing "special"....and conservatory maybe does, but extensions are the same as the rest of the home....WTF is the point of a "part time" extension....

Dingdongler

If that is the case and the walls and roof are made to similar spec to your house ie cavity insulated then one big radiator should do the trick.

What lots of people do is due to budget constraints they build a conservatory with lots of cheap glass and small (?uninsulated) walls. Some people specifically want what a conservatory offers but most actually want more living space but think the conservatory will provide this with less cost and hassle.

They then end up with a room that is cold in winter and like a sauna in summer so ends up becoming a glorified storage cupboard.

f1_fan

iTrader: (9)

Spot on post. Just build it to the same standard as the rest of the house and as jonc above said use Pilkington K glass and you should have a true extension that needs one appropriately sized radiator and nothing more.

jonc

The problem with double skinned insulated cavity walls is that they are quite thick and really eat into the floor space. The finished wall would be about a foot thick. This is why I favoured a timberframe contruction with high quality insulation. Its half the thickness and just as well insulated.

Dingdongler

For my own education do you have any idea how the thermal value of your timber frame construction would compare to an insulated cavity wall type?

Thanks

ALi-B

iTrader: (1)

Underfloor heating piped off the central heating. IMO.

However with a proper roof it'll alot more thermally efficient than the average conservatory/flat roof extension. So you'll probably be fine with a big double convector radiator.

Just make sure its sized right: http://www.plumbnation.co.uk/heating-calculator.php

If in doubt, fitthe next size bigger to what the above says and fit a high quality TRV (eg Honeywell VT200E )

jonc

I have no idea of the thermal values. My builder at the time assured me that with high quality insulation used in the timber frame, it would be similar to a cavity blockwork wall for half the thickness. I did google timber frame vs blockwork at the time just to double check.

gravy88

There is cheaper ways of doing underfloor heating. ( i.e without a expensive manifold )

You can just run it off the heating pipes. It would be a case of connecting on and bringing a pipe up through the floor with a TRV ( thermostatic radiator valve ) and back down under the floor and around the leg and back.

You could lay the pipes in screed, or you can even just clip the pipes to the joists and insulation between the joists. Thers lots of different ways of doing it, just depends on your budget. Have a look at http://www.polypipe.com/polypipe/con...categoryID=162 for some ideas.
Electric UFH is very expensive to run, and a lot of customers i work for never use it as it costs way too much.
Safest bet is to get a rad in there, tiled or wooden floors are always cold!

ChefDude

We have a 2m trench radiator in our living room. Very tidy and warm.