French Bay House Case Study

French Bay House Case Study


The French Bay House is a ‘typical’ Titirangi home, a unique cabin style infrastructure situated on a steep slope. The challenges created by this type of construction are the large spaces between the floor and the ground, which create significant draughts in windy conditions and the exposed gabled roof, which reduces the insulation choices. In addition, the floor and ceiling joists were not evenly spaced and in the roof, they were often greater than 700mm apart. The owners of the French Bay House, Ryan and Deidre, already painstakingly completed insulating part of the house with polystyrene and so when they were selecting insulation for the remainder of the home it was important that it would be easy to install.


Ryan said: “Our circumstances were difficult because our gabled roof provided no ceiling space for conventional insulation. The nature of the building also meant that space between roofing joists were not uniform.

We also knew we would be working overhead, so it was important the insulation used would perform well and be safe to handle with minimal irritation. Earthwool® glasswool ticked all those boxes.”

Earthwool® glasswool insulation: Ceiling batt, R4.1 was installed in the ceiling, providing the owners with excellent thermal performance. The rigidity of the ceiling batts also meant they could be turned sideways and friction fitted between joists that were greater than 580mm.

“The floor insulation needed to be able to withstand significant wind gusts below the house and so when we discovered that Earthwool® glasswool underfloor insulation was available with a wind-wash barrier, it was a no brainer that we needed to use this product,” said Ryan.

Earthwool® glasswool insulation: Underfloor roll with a wind-wash barrier, R1.8, was installed towards the outer edges of the floor, while Earthwool® glasswool insulation: Quilted underfloor batt, R1.5 was used towards the back of the house where the space was a little tighter to work.

Earthwool® glasswool insulation: R1.5 DriTherm® Masonry slab was used not only as it met the specific size requirements, but also due to its excellent thermal and acoustic performance. The external walls featured Earthwool® glasswool insulation: R2.8 Wall batts. This high rated insulation absorbs external sound transfer while ensuring a comfortable indoor temperature is maintained all year round. The Motel’s ceilings were insulated with Earthwool® glasswool insulation: Ceiling batt R3.6, creating a complete thermal envelope.


“Having already painstakingly completed one portion of our home with polystyrene underfloor insulation, it was so nice to finally work with Earthwool® glasswool insulation, as it was soft to touch, easy to cut and install and eliminated the issues we had previously with the polystyrene,” said Ryan.


Download the Case Study here.