Installation guidelines for ventilated floors

Additional insulation for a ventilated floor

From above

	Remove the floor and inspect the condition of the old insulation and structure. If the old structure and insulation are in good condition, just add new insulation layers on top of them. If they are wet or mouldy, remove then. In this latter case, pay special attention to the structure and observe what kinds of repairs are needed. Check the condition of the wind protection slab as well as the base. Remove all organic material (e.g., pieces of wood) from the base. Check that the base is well ventilated. Lay plastic sheeting on the ground to prevent moisture from rising. Leave a space of 100 mm at the edges. Place stones on the plastic sheeting to keep it in place.
	Add at least 200 mm of insulation above the base. If existing joists are not high enough for the new insulation, install studding.
	Nail supports to the joists and lay a wood fibre board on the supports as a blind floor. Insulate each joist slot so that the top of the insulation slabs is 10-20 mm above the top edge of the joist. Check that there are no gaps.
	Install an air or vapour barrier. Nail or screw new chipboard or wooden floor to finish the surface.

From below

	Remove the blind floor and all existing insulation
	Check that there is space for 200 mm thick insulation. Attach new joists if necessary.
	Install PAROC eXtra slabs between the joists and check that there are no gaps. Select the thickness so that there is an excess of 10 mm. Secure the slabs in place with a plastic strap before installing the wind protection slabs.
	For a wind protection slab, use PAROC WPS 3n or PAROC WAS 25t. Fix it with nails and washers.
	Remove all organic material, such as pieces of wood, from the base. Check that the base is well ventilated with vents. Cover the ground with plastic sheeting to prevent moisture vapour from rising. Place stones on the plastic sheeting to keep it in place.