This is a question we get asked a lot, and there’s no easy answer! Insulating your home can be a great way to keep warm and cut your bills, but with such a huge range of materials on the market, knowing which to choose can be really difficult. The final choice as to whether to use insulation slabs or rolls is yours, although it mainly depends on the application – are you using it in the loft, walls or floors? Another thing you’ll need to take into account is your budget, and (if you’re doing it yourself) your DIY skills.
Installing insulation between the joists will create what is known as a cold loft. This means you lay the insulation on the floor of the loft, preventing heat getting into the loft space. If you just use your loft for storage, and you don’t have a room in the roof, there’s little point paying to heat it. In this case, it’s quite an easy DIY job to just roll insulation out and then trim off any excess. If you’re using roll insulation, and you’re planning to keep stuff on top of it, you will need to put boards on top, without squashing the insulation, as this will affect its performance! Slabs are more expensive but mean you can store things straight on top. So it really depends what you use your attic for.
If you go for a warm loft instead, this means insulating the rafters. Although again it is a personal choice, it may be easier to use insulation slabs rather than rolls. This is just because of gravity really. It’s probably going to be easier to install semi-rigid slabs above head height than it is to try to attach insulation from a roll, and then having to put netting underneath it to keep it in place. Slabs are pretty easy because they can be cut to size and fit snugly side by side.
If your property has solid walls, cavity wall insulation is not an option, and you may not have the budget for external wall insulation. Insulation can be installed on internal walls, but there are quite a few things to take into account: how much space are you willing to lose, and how much work do you want to put in? You will also need to think about whether you need a damp proof membrane, or a stud wall.
Slabs can be glued directly to the wall, and provide a flat surface to plaster over. Some slabs already incorporate a vapour barrier too, so can be a straightforward and structurally wise choice. Although rolls of wool can also be effective if installed properly, wool will encroach more on your room space, and installation will be more complicated.
What kind of insulation you can use for floors depends on what kind of floor you have. If you have floorboards, you can lay wool or semi-rigid boards under the floorboards between the joists. If you’re insulating a solid floor, you can obviously only lay insulation over the top of it. You will have to use fully rigid slabs for this, because fibres in any other kind insulation will compress when you walk over it – and most people don’t want a squashy floor! You can then put chipboard over the top to finish the job. You will lose some of the height of your room doing this, and it’s also recommended to carry the measure out across a whole floor, or you’ll end up with different floor levels in each room.
If you need more information on choosing the best type of insulation for your project, just give us a call and we’ll be happy to help!