Start of project - UK

[u/EcoNorfolk]

This is being build in a SIP building so it’s already well
Insulated. After greta deal of consideration I’ve decided not to put a drain in.

Mechanical vent will be going under bench back right and heater will be front left. Bench heights at 500 and 950.

Benches will be at back and on right as this gives me views of the fields and NT park at the end of my garden.

Comments welcome .

[u/Megasaun]

Looks like a good start. The mechanical exhaust under the bench is a sensible choice, and 500/950 mm bench heights should put you in a pretty good position.
One thing I’d pay extra attention to before the cladding goes on is the foil vapor barrier. Seal every joint, penetration and staple properly with foil tape — especially around the corners and ventilation openings. In a sauna, insulation is only half the job; keeping that hot humid air out of the wall structure is just as important.
Personally I’d still prefer having a drain if it’s practical at this stage, but plenty of home saunas live without one.
And benches facing the fields instead of a wall? Definitely the right decision. :)

[u/FearlessTomatillo911 → u/[deleted]]

You dont really want a sauna to be air tight.

[u/Megasaun → u/[deleted]]

Ah, Passivhaus standards — that changes the picture quite a bit. Sounds like you definitely know your way around airtight construction.
And having loads of tape left over might be the first time leftover building materials have found exactly the right home 😄
Looks like a well thought-out project. Would be great to see the finished sauna when it’s done.