Heating in a conservatory: thoughts please

[Lindyboo]

We’re planning a small conservatory for our tiny shack – bod coming next week to measure up – and I’m clear on most things that I’ll want, but don’t know if it’s worth having heating installed. Years ago I had a single-glazed conservatory and made do with a portable heater but of course most of the heat quickly disappeared. The new one will be double glazed and have a glazed roof. Should I still expect a great heat loss? My thinking is that if modern conservatories retain an acceptable level of heat then it'll be worth adding an extra radiator onto the existing heating system.

 

[jocelyn plummer]

Would it be worth considering an independent underfloor system-- you could control it as required.

 

[Keithj]

You may find, if you have to get building regs approval for it (we did, for our garden room - the same concept but with a tiled roof) that the thermal insulation is defined for you.

With that in place, the heat loss in winter is surprisingly low. We installed two electric skirting heaters (I think about 4kW each). We've only ever needed to have one of them switched on.

Underfloor heating is great for rooms you expect to use a lot, every day. It takes a while to heat up, and a while to cool down, so is less flexible than radiators or skirting heaters for rooms used only occasionally.

 

[stuart45]

You don't usually require PP or Building Regs for a connie. However if it's heated from the main system Building Control will probably call it an extension and in theory it will require regs. General rule of thumb is that 75% of roof and 50% of walls are glass or similar, it's not heated from the main system and there is an external grade door between it and the house.
However many people ignore this and it only comes up in a sale, sometimes.

 

[Lindyboo]

Thanks all for your thoughts. I wondered about the underfloor option, but my fundamental pondering was the heat loss factor, which will apply equally to any heat source. If modern conservatories of the style I’m after lose heat significantly then I’ll be inclined to save my pennies (I’m originally from Yorkshire, so the inclination is genetic) and forego installed heating for a portable job. No doubt the conservatory bod will have something to suggest, but I’m interested in the experience of forum members before I get the ‘sales pitch’ next week.

Ta v much.

 

[88v8]

More immediately, make sure it's built with good ventilation, especially if it's on a south wall otherwise it will just be a sweat box.

Our conservatory had four automatic roof vents, and four manual 'gunports' in the walls so there was constant flow of cool air, and it was fine. It was also helped by a good stand of hazels that gave shade from the direct sun. So many conservatories are built with no ventilation, or just an opening window which is pretty useless as one can't leave it open when not there, and then they sell you expensive blinds which inadequately compensate for the useless original design of the building.

As to heat, it was wooden, double-glazed. I built in two fan heaters, each 1kw, linked to a separate room stat, and they comfortably heated it and kept it above 40F in winter.
It was 16' x 7' average x about 9' high, so about 1,000 cubic ft.

Ivor

 

[Lindyboo]

Thanks 88v8, good point about ventilation. The one I had years ago faced south which sounded a good idea but was unusable in high summer and ventilated only by a window. It got so hot in there one day when closed up, that the thermometer, which maxed at 124 degrees, exploded!

The size of the one you mention will be about the same as the one I have in mind, so that’s useful info on the heating. Ta.

 

[Flyfisher]

Yes, good ventilation is vital for temperature control.

We had a conservatory at our previous house. The first summer after we had moved in and not being familiar with its operation, we closed it all up to go away on holiday and didn;t even draw the reflective roof blinds. When we returned two weeks later, the plants were burned to a crisp and the table candles (we used it as a dining room) had turned into pools of molten wax!

And this was a north-facing conservatory in a heavily-wooded plot.

 

[LadyArowana]

We had a conservatory at our previous house. The first summer after we had moved in and not being familiar with its operation, we closed it all up to go away on holiday and didn;t even draw the reflective roof blinds. When we returned two weeks later, the plants were burned to a crisp and the table candles (we used it as a dining room) had turned into pools of molten wax!

.

That sounds like a nice comfy temperature to me, I could probably manage without a woolly jumper.

 

[Penners]

Our conservatory had ... four manual 'gunports' in the walls

I never realised that Gloucestershire was so dangerous. The natives are quite friendly in Suffolk.

We have a modest conservatory with double-glazed windows and roof. It has no heating facilities and we don't mind this. If the temperature in the conservatory is lower than in the house (on cold winter days, for example) we simply don't go out there. Nevertheless, it does still remain warm enough to protect tender pot plants.

However, we often find that on sunny winter days the conservatory gets warmer than the rest of the house.

By the way, I suggest that you don't double-glaze the French windows between the house and the conservatory (assuming you will have these). Single glazing allows a trickle of heat to leak out from the house into the conservatory, just to keep a little of the chill off it.

 

[Penners]

That sounds like a nice comfy temperature to me, I could probably manage without a woolly jumper.

Mrs P couldn't. For her, there are only two temperatures: "nice and warm" and "freezing". The former seems to occur for a few hours in August every fourth or fifth year.