Russian Banya
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Research into the construction of a Russian banya (or Finnish sauna) - a necessity for any home. Construction has not yet begun.
Model
Banya plans. Note that no windows or doors are indicated yet.
Foundation
There are two types of above-ground structural foundations: pier or skid
- pier involves vertical posts upon which the foundation rests.
- skid involves laying a foundation directly on the ground
- in either case, make sure string outline is square by measuring diagonally from corners
Pier foundation
- lay out outline of walls w/ string
- mark out every 4 feet along string
- dig 12” below frost line (check village inspector about depth of frost line)
- bury treated 6x6 posts or sona tubes (tubes filled w/ concrete)
- attach/set anchor bolt in center of each post
- attach 6x6 post to anchor
Skid foundation
- simplest type
- no digging necessary
- consists of treated 4x4 or 6x6 lumber
- lay out lumber the length of cabin
- space out according to standard
- floor joist spans dependent upon lumber type
- consider deck blocks with floor posts inserted into them underneath floor joists
- see http://www.finehomebuilding.com/2003/04/01/a-firm-foundation-for-a-backyard-shed
Size
- no taller than 7’, otherwise lower areas do not retain heat as it rises
- 8’x10’ fits 7-10 people
- 5’x7’ and 6’x7’ popular for home, fits 3-5 people
- inside dimensions should be multiples of 12” for standard tongue and groove interior boards
Floor
- doesn’t need insulation
- plywood subfloor paint or waterproof sealant
- durarock covered in a coat of vinyl cement repair, or simple cement tile, cement, tile, or something that won’t absorb water on top
- duckboard floors are often placed on top
- removable sections of 1”x3” or 1”x4” wooden slats with 1/2” spacing between the slats
- cut shower drain in center, ideally sloping floor towards drain
- can use vinyl cement patch 40lb and trowel it onto subfloor 3/4” around perimeter, sloped to 1/4” at drain
Framing
- frame with 60”x84” space between wall studs
Wall framing
- 2”x4”s for headers and plates
- 2”x4”s for framing studs
- make sure your spacing of studs works for whatever sheathing material you are using
- place load-bearing wall studs 16” apart and non-load-bearing studs 24” apart
- start by marking the bottom and top plates every 16” (except first and last marks, which are 15.25” from nearest mark)
- note that the so-called 2”x4” is actually 1 1/2” by 3 1/2”
- add horizontal supports between studs at height where benches can be screwed in
- secure all frame joints with two 3 1/2” nails
Roof framing
- run roof rafters longer than needed
- cut “birds mouth” slots into rafters where they sit on top of wall top plates
- can bolt rafters to walls with hurricane ties
- stove pipe thimble can insulate and space the stovepipe where it goes through the roof
Windows
- use only single glazed tempered glass, not double-glazed because they fog up
Door
- opens outwards
- standard = 24” x 72”
- rough opening = 26” x 75” (1/2” more on each side than actual door size for wiggle room)
- headings are 1” wider than door on both sides, plus another 3” extra total
- handle made of wood
- non-metallic door catch available from sauna dealers
- leave air space below door of 5/8” to 1” for oxygen
Vents
- intake vent below heater near floor
- exhaust vent towards the ceiling on other side of room
- perhaps a second exhaust under the benches
- 3”x10” duct space
Insulation
- high-temp aluminum foil vapor barrier with shiny side in (Type C single-side foil)
- start from bottom of wall and work up so higher sheets overlap lower ones
- use aluminum duct tape to cover seams and tears`
- conventional fiberglass insulation batts (usually come in 15” widths for standard stud openings)
- R13 for walls
- R22 or R26 for ceiling
- can put two layers of R13 laid in perpendicular orientation`
- consider recycled cotton insulation rather than fiberglass, because it’s easy to work with and non-toxic (brand name UltraTouch by Bonded Logic)
- floor doesn’t need insulation
- caulk bottom of walls meeting floor
Interior
Wood and nails
- deciduous trees
- western red cedar, aspen, spruce, hemlock, pine?
- some varieties may leak melting sap which can hurt
- tongue and groove boards of 1”x4” or 1”x5” nominal widths
- with the grooves facing down so water can’t collect into them
- galvanized 1.5” nails
- 5D galvanized small head siding nails
Heater
- drum stoves are popular because doesn’t require welding.
- preferable to feed wood from predbannik, although more complicated to run stove through wall
- volcanic rocks placed on top of heater to retain heat
- wire mesh to hold rocks in place
Benches
- use thick 2”x2” or 2”x3” or 2”x4” planks
- avoid knots in wood since these heat up more
- fastened w/ screws on underside
- two-tiers
- L-shape?
- long enough to stretch out
- generally allow two feet of bench for each person on the upper bench
- 1/2” gap between planks
- lower bench should be 18” from floor and 17” deep for strength
- upper bench should be 18” higher than lower bench, about 3 1/2
- 4 ft from ceiling and 20” to 35” wide for comfort
Lighting
- lighting should be discrete and not cast shadows
- 60W light bulb, weatherproof and heat proof encasement
- or follow Finnish tradition with a candle window between the predbannik and the banya
References
- http://www.saunatimes.com/category/building-a-sauna/
- http://www.saunatimes.com/category/building-a-sauna/stoves/page/2/
- http://homesaunakits-since1974.com/Sauna-Building-Aids/106-sauna-building-how-to-build-a-sauna.html#1-buy-a-sauna-kit-to-do-it-yourself
- framing tips: https://www.mycarpentry.com/framing-carpentry.html
- https://web.archive.org/web/20060126211339/http://cankar.org:80/sauna/building/design.html
- tour of 8x8 sauna: https://www.youtube.com/watch?v=56nP5u3FAbI&t=333s
- tudor shed plans: https://www.buildeazy.com/plan_links_sheds.html
- pretty shed: http://www.livingroofsinc.com/wp-content/gallery/s-h-e-l-t-e-r/p4190156-copy.jpg
- stove clearances: https://cdn.shopify.com/s/files/1/1661/5331/files/nippaInstallManual.pdf?3150570655419202463
- cross-section of shed design: http://shedplanspackage.com/wp-content/uploads/2013/11/work-shed-designs-2.jpg
- nice overview of building features: http://bouldersauna.com/
- kit company with useful layouts: http://www.finlandiasauna.com/pdf/Finlandia_Sauna_Brochure-WEB.pdf