Heating a 20sqm outbuilding in the winter - what do i do ?

For Info. The Chinese diesel air heater does not have a water boiler and is not the same as mentioned earlier. These are air heaters only and as such are suitable for buildings with the appropriate and proper installation. The YouTube videos show installations.
 
Sponsored Links
I'm wondering about your doors and windows? also draughts? and do you have any thermal mass in the room?
If it were me I'd be looking first at draughtproofing and increasing insulation, rather than changing the heating...
 
...Its a big open room 3.1m x 6.5m...

Consider building an insulated stud wall to make your heated area smaller. A desk plus filing area may be as small as 2m x 2m.

Its costing an absolute fortune, my electricity usage is about £5 extra a day anytime I work out of the outbuilding.
Hmmm? At about 20p per kWh you must be using 25 kWh per day, about 2.5kW average for a ten hour working day. That's a lot of heat to lose from a 'well insulated' building.

Have you considered a 4kW air source heat pump? For 1 kW of electrical power you can enjoy 'about' 3kW of heat in winter, and 4 to 5 kW in spring and autumn, so you'll spend about £2 per day to run it, using your figures. Because they blow warm air the room will appear to warm up quickly, and they can also be used to give comfort cooling in the summer. Capital costs are coming down, though a decent branded ASHP will cost up to £1500. If you're fitting it yourself you MAY need a certified f-gas fitter to commission it, though if you buy a fitted package you'll pay more but may be able to get funding via the Green Homes Scheme announced last summer.

ASHPs are about as noisy as a large 'fridge, and that may be important to you, but certainly no intrusive to normal conversation.
 
Is that factory or aftermarket. Any idea which model?

It was an original factory fit, but by the time they built my car, they had changed it to an option at £1000. It was all plumbed and wired up for it, just lacking heater and the dosing pump, which I managed to track down for £100 second hand. Only took an hour to fit. It comes on auto, if the outdoor is <4C and the coolant is <77C when I start up, I modified it, so I can turn it on manually to warm the car up before I get in. You can buy an option to turn it on at pre-set times, another option to wireless remote control it, then yet another option to be able to send it a text to turn it on.

I will try to remember the model and post details later.
[EDIT] It's a Webasto 98570B heater.
 
Last edited:
Sponsored Links
I'm wondering about your doors and windows? also draughts? and do you have any thermal mass in the room?
If it were me I'd be looking first at draughtproofing and increasing insulation, rather than changing the heating...

All the windows were newly installed a few months ago, there is a door leading to a toilet (extremely cold toilet and the tiled floor makes it worse so I keep this door shut), the seals by the french door appear to be fine being a big open room doesnt help as it means the heating is not concentrated to one place and I do not wish to divide it. The only insulation I feel I can increase is that of the loft, is there a way to know if that is where heating is being lost ? Just wary of barking down the wrong tree, although I can buy extra 200mm thick top up insulation, it doesn't harm to do this.
 
I have also noticed that underneath the skirting is like a 1mm gap, should I be filling this up because I dont think the insulation starts that low. In terms of filling it up, should this be silicone or caulk ?
I say this because in another part of the main house, we noticed draught coming in from underneath the skirting.
 
The only insulation I feel I can increase is that of the loft, is there a way to know if that is where heating is being lost ?

Work out the areas of roof, wall, window/door and floor.
Estimate U-values.
Calculate likely heat loss through each.

This should be accurate enough to suggest where insulation would be most useful, and whether or not you have some unexplained heat loss somewhere.
 
Is there a device one can buy like a heat map thing that will just show you where the heat loss is happening ?
 
just one observation, when I sit under the desk, my feet is freezing as I try not to wear shoes inside to keep the place clean, so i am suspecting the 1mm spacing between skirting and the vinyl laid on the floor. I am guessing I can use a tub of flexible clear silicone underneath and this should stop draught from coming in, thinking about it, if the theory is right, thats almost 16m of skirting where draught could be coming in from.
 
Is there a device one can buy like a heat map thing that will just show you where the heat loss is happening ?

A contact-less thermometer, which can be bought for a few pounds on ebay, will allow you to quickly find the cold spots in a room - it needs to be cold outside and warm in the room, to best show it up and they work best 'looking' at a black surface - black insulating tape.

It is best done on a dull day, when there is no local solar heating. Using one, you can mark on the diagram of the room, the temperatures within 0.1C and thus see where your heat is going. The alternative is a more expensive thermal camera, but you can get an attachment for a Smart Phone.
 
Morning All.
A contact-less thermometer, which can be bought for a few pounds on ebay, will allow you to quickly find the cold spots in a room - it needs to be cold outside and warm in the room, to best show it up and they work best 'looking' at a black surface - black insulating tape.

It is best done on a dull day, when there is no local solar heating. Using one, you can mark on the diagram of the room, the temperatures within 0.1C and thus see where your heat is going. The alternative is a more expensive thermal camera, but you can get an attachment for a Smart Phone.

Consider building an insulated stud wall to make your heated area smaller. A desk plus filing area may be as small as 2m x 2m.


Hmmm? At about 20p per kWh you must be using 25 kWh per day, about 2.5kW average for a ten hour working day. That's a lot of heat to lose from a 'well insulated' building.

Have you considered a 4kW air source heat pump? For 1 kW of electrical power you can enjoy 'about' 3kW of heat in winter, and 4 to 5 kW in spring and autumn, so you'll spend about £2 per day to run it, using your figures. Because they blow warm air the room will appear to warm up quickly, and they can also be used to give comfort cooling in the summer. Capital costs are coming down, though a decent branded ASHP will cost up to £1500. If you're fitting it yourself you MAY need a certified f-gas fitter to commission it, though if you buy a fitted package you'll pay more but may be able to get funding via the Green Homes Scheme announced last summer.

ASHPs are about as noisy as a large 'fridge, and that may be important to you, but certainly no intrusive to normal conversation.


Morning All.

Thermometer should be arriving this week hopefully, what I did over the weekend was to look at the fabric of the building to see where the heat is being lost. I looked into the loft, I noticed that the cavity insulation was not continuous up till the tip of the ceiling, there was a 150mm gap between where the cavity insulation stopped and the base plate for the rafters, so I cut some cavity insulation and filled it up, I also topped up the loft insulation as i think when electrical work was being done up there, some of it were displaced, arranged nicely into the joists and overlapped with a 200mm topper.

I am sure this will make some small difference, I was told that Air to air heat pump is the solution going forward, but would not be eligible for the government scheme as the area was too small for the scheme that is covered by the government scheme. From my research, air to air heat pump can cost about 1k - 2k. I need to work out how many Kw capacity I need and whether air to water is better or air to air, I do have a bathroom/toilet in there, but thats already plumbed with a water tank cylinder in the loft and not sure if I want to disrupt that at the moment.

The heating is the priority.
 
...From my research, air to air heat pump can cost about 1k - 2k. I need to work out how many Kw (do you mean kW?) capacity I need and whether air to water is better or air to air...

The output requirement is about the same as for ANY heating system but, as the air to air heat pump can get away with producing lower temperature air (25 Celcius) rather than the 60 + for a wet radiator system, then I would go for the air to air heat pump....less chance of freezing up, quicker to warm up, capable of delivering useful heat at lower outside temperatures, and probably cheaper than air to water.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top