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Articles and Further Information

How to install Warmcel 100

Warmcel 100 is non-toxic and non-irritant to eyes and skin. However it does cause a small amount of dust when pouring. Therefore we recommend you wear a dust mask.

Before you start laying Warmcel 100:
  • Make sure you have a sturdy pair of steps or ladder to get into your loft.
  • Arrange for adequate lighting in the loft.
  • When in the loft make sure you do not tread between the roof joists, otherwise you could not just damage yourself, but also your ceiling. Try to get a crawling board into the loft to span the joists.
  • Make sure the loft is as clear as possible.
  • If you have any pipes going through the ceiling to the room below, fill any gaps around the pipes with stiff card, or mastic sealant.
  • Put guards around any fluepipe or recessed light fittings to keep Warmcel 100 approximately 150mm away from any hot component. Either build a wooden box with an open top round each light or cut a length of 150mm PVC plastic pipe around each light. You can also install fire-rated recessed light covers.
When laying Warmcel 100:
  • Make sure you do not cover any ventilation grilles/holes at the eaves of the roof. We can supply PVC Eaves Ventilators which can be cut to any size - no fixing required - and which will hold the Warmcel 100 in place. For more information please contact us. Alternatively cut hardboard to fit between roof timbers at eaves to stop Warmcel 100 blocking ventilation to roof.
  • If you have any electrical cables running across the joists try to leave the cables above the Warmcel 100. High amperage rated cables (shower and cooker cables) must be kept away from any insulation material.
  • If you have a cold water tank sitting on the joists, then do not insulate under the tank.

Start laying the insulation in the far corners from the loft hatch, making sure you get to all the difficult corners.

The insulation is loose. Make sure you 'fluff up' the Warmcel 100 with your hands as much as possible as you take it out of the bag. This enables air to be trapped in the insulation. Any compression of the insulation will reduce the efficiency.

If possible lay the insulation over the joists as this reduces the heat loss further.

Once you have put all the bags of Warmcel 100 in the loft, fix the polythene loft hatch apron. The apron will stop dust falling into the room below and will stop Warmcel 100 being disturbed around the hatch in future. When you have finished the work, cut around loft hatch to get out! Make sure you take a knife with you into the loft.

Do not forget to insulate the loft hatch itself. Fill a polythene bag with Warmcel 100 and stick or staple it to the hatch.

If you do not have a draught proofing seal where the hatch fixes to the ceiling, now is a good time to fix one. Approximately 2% of energy lost through a loft is via the loft hatch.

If the insulation gets wet from a leaking roof etc. it should be removed. This is easy with Warmcel 100 as you can remove the wet area and even dry out the material to fill the gap.

Each order comes with a free hatch pad kit and full installation instructions.