Heating for all year round summerhouse.

[Mastbruch]

I've wrote a question before regarding this but I've sort changed my plan sort of.

Insulated & boarded large summerhouse so far with 60mm insulation and duplex foil back plasterboard, but as for heating it and cooling it would anyone suggest sticking in a portable Air Condition unit which will give warm and cold air and dehumidify.

Or

Buy 2 oil radiators or 2 oil free radiators with thermostat and buy a separate dehumidifier.

Both ideas work out around the same price for materials/units.

Cheers.

 

[SimonH2]

In theory the A/C unit is cheaper to run for heating - but you need to read the detailed technical specs to find it's heating performance when the outside is cold. Most heat pumps drop off in performance (and efficiency) as the source air gets cooler - so most air source heat pumps drop in efficiency to the point where direct electric heating is the same price. Of course, this cold weather is also when you most want the heat.

Don't take claims like "uses 1/3 of the electricity" at face value - it's VERY dependent on conditions and the manufacturer will be happy to use figures that make their kit look good.

But it also depends on your planned occupation pattern. If it's going to be occasional and you plan to just heat it when you go in, then something that blows warm air will probably feel warmer quicker. But bear in mind that the AC unit won't provide any dehumidification except when cooling - so you might possibly need the standalone dehumidifier to keep the damp at bay.

 

[Mastbruch]

In theory the A/C unit is cheaper to run for heating - but you need to read the detailed technical specs to find it's heating performance when the outside is cold. Most heat pumps drop off in performance (and efficiency) as the source air gets cooler - so most air source heat pumps drop in efficiency to the point where direct electric heating is the same price. Of course, this cold weather is also when you most want the heat.

Don't take claims like "uses 1/3 of the electricity" at face value - it's VERY dependent on conditions and the manufacturer will be happy to use figures that make their kit look good.

But it also depends on your planned occupation pattern. If it's going to be occasional and you plan to just heat it when you go in, then something that blows warm air will probably feel warmer quicker. But bear in mind that the AC unit won't provide any dehumidification except when cooling - so you might
possibly need the standalone dehumidifier to keep the damp at bay.

Thanks for the reply, it's going to be used daily all year wrong as it's a games room with pool table, would you yourself just buy an electric oil free or oil radiator or 2 of them and a seperate dehumidifier?

Cheers

 

[AronSearle]

Why so little insulation if you intend to use it a lot, Seems ridiculous to use so little and then wonder about which is the cheapest heating/cooling method.

Also, overhangs above the windows to prevent direct summer sun, and more insulation will keep it cool, or at least mean a significant reduction in the use of air-con.

And why do you think you need a dehumidifier, I don't see any need for it?

 

[Mastbruch]

Why so little insulation if you intend to use it a lot, Seems ridiculous to use so little and then wonder about which is the cheapest heating/cooling method.

Also, overhangs above the windows to prevent direct summer sun, and more insulation will keep it cool, or at least mean a significant reduction in the use of air-con.

And why do you think you need a dehumidifier, I don't see any need for it?

When you say so little insulation not sure what you mean? It's completely slabbed out between every joist.

 

[AronSearle]

60mm is not a lot of insulation.

 

[noseall]

Insulated & boarded large summerhouse so far with 60mm insulation and duplex foil back plasterboard, .

What kind of insulation?
I would recommend 60mm foam board (Celotex, Kingspan etc) between studs and another 60mm across the outside face of the studs and wrap the lot in breathable membrane, prior to cladding.

If for example you have only fitted 60mm of fibreglass then this is woefully short.

If you have only fitted 60mm of foam board between, then you are going to get cold spot bridging and it will struggle with hot and cold weather.

 

[Mastbruch]

60mm is not a lot of insulation.

But the studs are only 75mm, so not sure how I'm suppose to stick thicker insulation in?

 

[noseall]

60mm is not a lot of insulation.

But the studs are only 75mm, so not sure how I'm suppose to stick thicker insulation in?

I would recommend 60mm foam board (Celotex, Kingspan etc) between studs and another 60mm across the outside face of the studs and wrap the lot in breathable membrane, prior to cladding.

 

[Mastbruch]

60mm is not a lot of insulation.

But the studs are only 75mm, so not sure how I'm suppose to stick thicker insulation in?

I would recommend 60mm foam board (Celotex, Kingspan etc) between studs and another 60mm across the outside face of the studs and wrap the lot in breathable membrane, prior to cladding.

Not sure if I'm not getting this or not, I've laid 60mm of insulation between the studs,where the plasterboard foil back is now is reading to be fixed on to the studs so I'm not using cladding internally,

Are you saying to use thermal board insulation on the internal walls instead of just plasterboard?

The normal operation is to fill studs with insulation and then add a vapour barrier or foil back plasterboard but you're saying about sticking more insulation on the outside of the internal walls that don't make sense

 

[AronSearle]

Insulation between studs.

Then more insulation to the outside or the inside face of the studs.

Internally you can use insulation backed plasterboard.

Externally you can use rigid insulation fixed to the outside of the studs, with cladding battens fixed through that, or batten and counter batten with some insulation between those.

 

[SimonH2]

Whichever way you do it, you want a vapour barrier on the inside. Without it, moisture from the relatively warm and moist inside will permeate through the insulation and structure. At some point the temperature will be low enough for condensation to form.

At best this will make the insulation start to smell, but it will most likely make the timber rot.