ᐅ New Construction: Insulation of Collar Beam Ceiling and/or Roof?

We are currently planning the new construction of a single-family house with a pitched roof. The attic will be used as the location for a gas condensing boiler as well as for storage. Access will be via a pull-down staircase.
Where would insulation be ideally placed?

• Only the roof (disadvantage: you also heat the attic in winter and the upper floor may get somewhat warmer in summer)
• Only the collar beam ceiling (disadvantage: no frost protection for the heating system)
• Both (disadvantage: cost)

Thanks to everyone.

The question does not arise; the heat generator must be located within the insulated building envelope.

Don’t you run into problems with mold if the roof is insulated but not ventilated? It’s hardly practical to go up daily through a retractable attic ladder to air out the space.

Regards,
Sabine

Curly schrieb:
Don’t you get problems with mold if the roof is insulated but not ventilated?

In new buildings, there is usually a mechanical ventilation system that can handle this. Maybe it is even installed up there?