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Things to do in your loft before you start

Clear the loft of any obstacles and clutter

This makes working in your loft much safer and allows you to work out what you need to buy.

Check that your loft is properly ventilated

Ventilation prevents problems like damp occurring in your loft. There will either be an opening at the eaves where the pitched roof meets the external wall or proprietary ventilators in the pitch of the roof. If neither are present then ventilation must be installed, and specialist advice should be sought.

Check what insulation is already in place

Most lofts have at least some level of insulation in them already, but it may not be enough. Building Regulations require at least 270mm of loft insulation: 100mm loft roll between joists and 170mm roll cross-laid on top. If you have insulation between ceiling joists already make sure it finishes level with the top of the joists. If not you will need to top it up. Cold water tank and pipes also need to be insulated. Insulating your loft makes the loft space much cooler as it is no longer warmed by heat escaping from the rooms below. This increases the likelihood of pipes and cold water tanks freezing in colder weather.

Tips on how to measure up

The following will make sure you buy the right materials for your project. Measure the length and width of your loft. If this isn’t practical to do in the loft, then measuring the floor below will give you the same measurements, as long as it's the same size.

Measure the size of your cold water tank, if you have one that isn’t insulated.

Measure the length and diameter of un-insulated water pipes that run through your loft if you have any. Diameter will be either 15mm or 22mm.

Count the number of recessed downlights in the ceiling below if you have any.

If you are adding some storage space in your loft as well as insulating it, measure the distance between your joists - typically either 400mm or 600mm. This will determine how many loft legs and screws you will need (see below).

Calculating how much you need

Loft roll

Top. 200mm roll is an option for a top layer instead of 170mm and gives you even more energy efficiency. If you have insulation between ceiling joists already make sure it finishes level with the top of the joists. If not you will need to top it up. Determine the area of your loft by multiplying the length by the width. Deduct 10% from the area for 100mm roll to allow for joists. Divide the area by the loft roll pack coverage to get the number of rolls required. The table below will give you a good guide. It is better to buy too much than too little loft roll, as any left over can simply be laid over the top as an additional top layer.

How much loft roll?
    2 Bed Semi/Terrace 50m2 3 Bed Semi/Terrace 60m2 3 Bed Semi 80m2
  Coverage Approximate number of loft rolls needed
100mm bottom layer 11.08m2 5 6 8
170mm top layer 6.47m2 8 10 13
200mm super top layer 5.61m2 9 11 15

Insulation for your cold water tank

Wickes sell two sizes which will fit most cold water tanks (see below). For larger tanks, instead of using a tank jacket, you can use a polystyrene sheet on the top of the tank and run the loft roll up the sides and tie in place using string.

  Tank capacity Width Length
4 gallon Tank Jacket 4 gallon (18 litre) 305 mm 457 mm
25 gallon Tank Jacket 25 gallon (114 litre) 559 mm 737 mm

Pipe insulation

Pipe insulation and is available to fit both 15mm and 22mm pipes and is sold in 1m lengths.

Downlight covers

For every recessed downlight you have in the ceilings below your loft you will need to fit a downlight cover. These will both prevent warm air leaking into your loft through the downlight but also protect from overheating and fire risk. To fit them properly you will need silicone sealant too, one tube should be enough for an average loft.

Calculating materials for new storage space

Determine the area of space you want to create, remembering that space with little headroom will be less useful. How many loft legs and screws you need will depend on the distance between your joists. The table below will give you a good guide:

Size of storage area 5m2
Approx. area of kingsize bed
Approx. area of transit van
Approx. area of single garage
Distance between joists 400mm 600mm 400mm 600mm 400mm 600mm
Loft storage panels
Pack of 3 (1.17m2)
5 5 9 9 13 13
Ultra gold screws
4.0 x 30mm. Pack of 200
2 2 3 3 5 3
Loft legs
Pack of 12
6 4 9 7 12 9

How to guides and videos

Floorign Inspiration Gallery

How to insulate your loft

If you want to make your home warmer and save money on your energy bills then insulating your loft is the first place to start. Take a look at our guide and video to see how quick and easy it can be to do yourself.

Floorign Inspiration Gallery

How to create storage space in your loft

Creating a storage area is an inexpensive and straightforward project, especially if you are already working in your loft.

Floorign Inspiration Gallery

How to draught-proof your home

Follow our easy how to guide and keep your home warm by fitting draught excluders around your doors and windows.