Ceilings and floors
One fourth of heating losses result from ceilings that are not insulated. Good thermal insulation helps to save energy and money. As a winter cap protects your head, thermal insulation protects your home.
Insulating the top ceiling really brings returns, but there is a lot to be considered:
- Finished attics: Provide 24 to 30 cm of insulation in the roof slope.
- Uninhabited attic and no finishing planned: Place 24 to 30 cm of insulation on the top ceiling.
- Non-walkable attic: Apply insulation rolls or insulating modules. Caution: avoid gaps.
- Walkable attic: Use stiff insulation material and cover it with flooring, avoiding gaps. It is best to install insulation in a cross pattern.
- Caution: Attics heat up significantly in the summer. Watch the position and size of attic windows.
- Flat roofs need to be insulated with 24 - 30 cm. If necessary, consult a specialist in your area.
- On insulating between rafters, ensure wind-tight levels, e.g., in the transition from the wall to the roof (see section Air tightness)
- Observe fire protection. Ensure that the top level is fire Brand retardant. On finishing an attic, the same applies for the roof and attic ceiling. Details can be requested from your building permit office.
- For houses with a basement, at least 10 cm of insulating plates on or in the basement ceiling (observe local ordinances).
- Option: hanging ceiling with insulation above.
- Basement pedestal: Moisture-proof thermal insulation at least one meter into the ground prevents thermal bridges. For new construction, continue thermal insulation along the complete basement walls.
- Insulate basement walls all the way down (avoid condensation in summer).
- For basements with water usage: vapor barrier for ceilings.
- For floor radiant heating, increase insulation because floor temperature is higher.
Depending on the desired types of floors and the planned floor covering, dry flooring or concrete can be used.
- Concrete compensates for unevenness in the substrate and provides a walkable surface that can receive the floor covering.
- For children’s rooms, sound insulation with concrete plates dampens noise passing into rooms underneath.
The most common construction types are:
- Bonded concrete (is used directly as a floor, e.g., for basement or garage)
- Concrete atop interface layer (separated from substrate via an interface to enable floating of concrete slabs with temperature variations)
- Floating concrete with floor covering (parquet, tiles, etc.). Suitable for radiant floor heating. It must meet the requirements of sound and thermal insulation.
Protruding building elements
- Important: Insulate ceilings above open portals, unheated garages, etc.
About noise insulation
- In general, for ceilings ensure footfall noise protection.
- Solid ceilings have better values, but a wooden rafter ceiling can match it due to multiple-layer construction.
- Noise protection for wooden ceilings: soft overlays on beams and posts prevent creaking; increased weight improves noise reduction (e.g., solid brick).
- For floating concrete: footfall noise reducing soft sublayer (caution with radiant floor heating).
- Separate concrete floors and wooden floors from walls and door frames.
- Use adhesion for radiant floor heating.
Poorly insulated ceilings sacrifice lots of heating energy.