In short, yes most garden room designs will be warm enough to use during the winter months, when we say most, we mean garden rooms that are built like timber frame houses with insulation in the floor, walls, roof and double glazing in the doors and windows – if you are looking at some of the log cabin style garden rooms or glorified shed construction buildings, its not so certain.
Modern garden room design takes its lead from timber frame housebuilding, in fact many of the building technologies you see in leading design programmes like Grand Designs have been widely adopted by the garden room industry, this makes garden room construction highly energy efficient.
Although not required by law unless a garden room is being slept in or is over 30sqm in size (garden rooms between 15sqm and 30sqm need to be sited more than 1m meter from the boundary line or be built of non combustible materials to not need Building Regulation approval). Many garden room suppliers design their buildings to meet and in many cases exceed the targets set by the Building Regulations.
It is important when looking at garden room specifications that insulation is specified in the roof, walls and floor, with some cheaper cabin style buildings there is no insulation in the wall structure, it is just solid wood, and whilst they rightly say wood has excellent insulative properties it is not comparable to a wall made up of layers of wood, insulation and air spaces.
The insulative performance of a wall, roof etc. is measured by the W/m2k this is com- monly known as the u-value. The Building Regulations set target u-values for new buildings and its a good idea to use these as a guideline when comparing specifications (see box right, its worth noting that the lower the u-value the better performing, so if your suppliers u-values are lower than the ones shown, it is exceeding the current regulations.
Part L of the Building Regulations was updated in 2014 and state these values for new houses, most garden room suppliers aim to meet or exceed these values:
Floor 0.13 W/m2k
Walls 0.18 W/m2k
Roof 0.13 W/m2k
Glazing 1.4 W/m2k
NB. The lower the figure the better performing.
Will I need a heater in my garden room?
High levels of insulation are the starting point for a comfortable garden room, the amount of natural warmth the building has will also be effected by the amount of heat it gets from the sun (see our guide to making the most from the sun in issue one of Garden Rooms Magazine), but our many years of experience in the garden room industry have found that an artificial heat source is still needed for the coldest days of the year.
A garden room is no different to any room in your house, would you be able to be in those rooms with no heat in the winter? Unless you have an air tight Passiv Haus we expect you have to flick the heating on, and your garden room will be no different.
It surprises us that some suppliers don’t include a heat source in their specification, even if it is never used, its nice to know you have it!
Like in a house you have several options from portable heaters to wood burning stoves. In our experience the best solutions are those that are designed in, in these cases thought is given to how the heating works with the room, underfloor heating for instance is great as it frees up floor space for furniture and big windows. Infrared panels can be discreetly fitted to the ceiling, again freeing up living space, and pipework and outlets for air conditioning can be neatly formed and hidden at the time of construction.
If your garden room doesn’t come with heating as standard you have lots of retro fit options which can be just plugged in and used such as oil filled radiators on wheels and electric fan and convector heaters.
You want a degree of flexibility with your heating, if you use your garden room for work a system with a timer is a good idea – set it for an hour before you start work and you’ll have a warm room when you arrive, but you also need the flexibility of instant heat if the weather suddenly gets cold so you can just flick it on.
Our advice would be to think of a garden room like you would any room in your house, don’t think of it as a shed that you need to sit and shiver in! Like a room in your house, low background heat makes it comfortable, but sometimes you need a bit more instant heat so make sure you have it!
To conclude, a garden room with good insulation and a heat source will be a wonderfully snug place to spend your time.