Roof
roof pitch
Drempel
Flat roof
Upper floor slab
Solid ceiling
timber-beamed ceiling
Nail binder
Attic conversion
External wall
Façade
Partition joint in a house
cellar wall
Ground floor
cellar ceiling
Stairway to the cellar
Solid ceiling
Cap ceiling
Timber joist floor/cavity
Special components
Many older buildings have a floor hatch with a built-in pull-down ladder, or simply a hinged cover that requires a ladder to be placed against it in order to open it, providing access to the loft. These are usually uninsulated and have draughts. As a result, a great deal of heat energy escapes in winter and a ‘chimney effect’ occurs, allowing indoor air to escape through leaky joints. The consequences are draughty and cold hallways and unnecessary energy losses.
The thermal break between the (unheated) loft and the heated interior consists of a wood-based panel, no more than 2 cm thick.
A perfect, but also labour-intensive and expensive solution is to replace it with a ready-insulated pull-down staircase.
A more cost-effective option, which can even be carried out as a DIY project, is to retrofit insulation using high-performance panels. These are simply stuck to the outside of the hatch cover. The result is perfect if the reveals are also insulated.
For leaky hatches, rubber sealing strips glued into the folds of the hatch cover provide a remedy.
The maximum possible insulation thickness should be selected (usually 3–4 cm)
All the benefits at a glance
Thermal insulation: Thermal transmittance coefficient of a floor hatch (U-value):
- before approx. 4 W/(m²K)
- after: approx. 0.6 W/(m²K)
This represents an 85 per cent improvement in the thermal performance of the floor hatch
Heating costs: The building’s heating costs are reduced. As this is a very small component, a significant reduction in heating costs cannot, of course, be expected. However:
‘Every little helps’!
Further advantages:
- There is no need for a labour-intensive removal of the old hatch.
- Structurally sound
- Draughts caused by leaks are eliminated
- the rooms feel cosier
- Heating costs are reduced
- CO₂ emissions are reduced
- This insulation method is very cost-effective and pays for itself within a few years
- The insulation work can be carried out in just a few hours
- Also suitable for DIY
Costs/value for money: If you have the floor hatch insulated by a professional firm, you can expect costs of around €150. If you do it yourself, the only costs involved are for the insulation, sealing tape, adhesive and new latches; these are likely to amount to around €30 per floor hatch.
Can I insulate it myself? Yes.
How is it done?
- Determine the maximum possible insulation thickness (this is determined by the space between the wooden panel and the supporting ladder structure).
- The wooden panel is glued over its entire surface to the insulation board (as with all insulation methods, there should be no air gap behind the insulation boards).
- Then you have yourself ‘locked in’ to the loft – that is, you climb into the loft and ask someone to close the loft hatch
- From above, the sides and reveals of the loft hatch are then insulated so that they are flush with the insulation boards
- Care must be taken to ensure a joint-free bond in each case
- Afterwards, you ask to be ‘let out’ again, and sealing tape is applied all the way round the edge of the loft hatch
- In most cases, it is then also necessary to fit a new ‘latch’
Time required: 2–3 hours.
Please note:
Subsequent use of the loft ladder will be more difficult because the wooden steps rest directly on the insulation board. Caution is therefore advised when using it!