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Is do-it-yourself loft insulation for you?

Here’s a quick checklist to help you plan a do-it-yourself loft insulation. But unless you’re a really keen DIY enthusiast, having the professionals install it for you is the safest (and cleanest) option.

How to install loft insulation yourself
(and why most people don’t)

Estimated reading time: 5 minutes

Loft insulation – not so easy to install after all

Installing loft insulation is easy, right? You just take out the old stuff, drag some new rolls up into the loft, lay it down and you’re all done.

Well, not quite. Of course, plenty of people do install their own insulation into cold loft spaces, but there are quite a few reasons why people ask us to do it for them.

It’s a messy business, involving heights, small spaces and sharp knives

You’ll need stable and secure access to your loft to make sure there’s no risk of trips and falls (we don’t recommend doing it on your own, especially as you’ll be up and down the ladder multiple times).

Make sure you wear a proper mask, one designed to the right specification to stop you from inhaling fibres and dust. You’ll also need overalls and gloves, and if there’s fibreglass involved, there’s likely to be a lot of itching, too – safety goggles can also be useful to keep it out of your eyes. Top it all off with a bump cap to protect your head from beams and the loft hatch frame.

You’ll be using a sharp knife to cut the insulation material to size, and we recommend making it a retractable one, which is safer for carrying around. You should be able to pick up all these items at your DIY store.

Falling through the ceiling is not a good look

You’ll need a crawl board: something sturdy to spread your weight over the joists so that you don’t fall through the ceiling (as well as being dangerous, it’s expensive, messy and embarrassing).

If your balance isn’t great, you hate ladders, or you’re not confident about moving around up in a confined space, fitting loft insulation is probably not for you.

Then, make sure the eaves are clear – this is essential for air circulation. They may be blocked by old insulation or newspaper. Newspaper used to be a popular choice for blocking eaves, but as it’s flammable, it must be removed.

Measuring and cutting insulation to size is easier than it sounds

Premium loft insulation is made from sustainable materials and is specially designed to be non-itch. This is important if you’re planning on accessing your loft regularly (for storage, for example). It’s also much less unpleasant to handle when you’re lugging it up into the loft space, unrolling it, cutting it to size, and putting it into place.

Even if the loft is tight for space, we’d suggest doing your measuring and cutting up there if you can, to avoid fibres and dust being spread throughout your living area. It’s not always easy on your own, which is why we work in teams.

The first 100mm layer should be laid snugly between the joists, fitting the gap exactly to make sure there are no bare areas. Get as far into the eaves as you can, covering the wall plate but not blocking the eaves ventilation (you can buy eaves ventilation trays to help maintain air flow, if necessary).

Hopefully by now, your knees are still in good shape, and you’re ready to put down the second layer. This needs to be laid at right angles to the first layer, covering the joists, adding another 170mm in depth, so overall you’re installing insulation that’s 270mm thick. Make sure that each strip of the second layer is tightly butted-up against the next, so there aren’t any noticeable gaps.

Finally – don’t forget the loft hatch. An uninsulated hatch door will allow heat to escape, so you’ll need to add insulation preferably to the same depth as the rest of your loft. You can usually do this by putting the required thickness of insulation in a bin liner and then stapling that to the hatch, making sure it’s ‘loft’ side is entirely covered.  Adding draught-proofing around the edge of the hatch will finish the job properly.

Your loft should now be a lot colder, so protect your pipes and tanks

Once your loft has been insulated to the correct standard, the average temperature will drop, as heat won’t be escaping upwards from your living area. This means that there’s a risk of freezing during colder months, so you may need to upgrade the lagging on all water pipes and water tanks in the loft space to make sure this doesn’t happen.

Finally (really finally this time) if your cold water tank(s) sit more than half a metre away from your loft hatch, you’ll want to fit a walkway or boarded area, as easy access may be vital in an emergency.

Don’t fancy it after all? We don’t blame you.

Book your free survey now and get a quote from Viridian.