precast concrete slaabing for timberframe

frankie2shoes

have recently ordered my timber frame and was wondering if anyone has fitted or knows anything about concrete slabbing for the outside face of the frame. it seems like a lot of trouble to go with blockwork to the outer face when all the insulation/strength is in the timberframe. i heard there were precast concrete sheets that can be attached to the front of the frame and then be rendered. can anyone enlighten me?

kadman

Attaching an external panel of PSME 65mm or better of expanded polystyrene
to the timberframe, and then applying a 35mm coat of external structural render to the galvanised mesh on the face of the panel, may be a better option than concrete slabbing.

kadman

Viking House

These systems can be used on the outside of your timber frames, fix the insulation directly onto the outside of the frames and plaster directly onto the insulation.

http://www.natural-building.co.uk/dtfm.htm

http://www.rockwool.co.uk/graphics/RW-GB-implementation/datasheets/RockShield.pdf

Put the OSB on the inside of the frames allowing them to sweat to the outside not trapping moisture like we normally do here. Tape and joint the OSB to achieve airtightness. This system gives a Passive Wall U-value of 0.15.

Excuse me Kadman what is PSME?

kadman

Hi Viking house,


The PSME is a single panel of 15kg-25kg density polystyrene 65 mm thick, with a galvanised steelmesh that is covered in a structural coat of 35mm
thick.Used worlwide for one off housing, apartment blocks ect 2 floors high with a single panel system, 3floors and more with a double panel system for the ground floor.




http://www.pasivna.com/pdfs/emmedue%20-%20izvedbeni%20sklopi.pdf


kadman

frankie2shoes

thanks for all the info/links. interesting stuff, but i'm not convinced of these systems strength/longevity on a once of build. my frame is coming cladded in ply to all external walls and is well insulated. a lot of these products seem to include insulation of one type or another. am a little concerned about their ability to carry weight, window sills etc. can't seem to find a load limit for them. also am a little concerned about their lifespan. one manufacturer spoke of 25 to 50 years which isn't even a lifetime (i hope). concrete slabs seem like a compromise between these products and more conventional block construction but i can't seem to locate a supplier. has anyone looked into the cost of concret slabs v block v composite slabbing?

galwaytt

Frankie - some points for you to consider;

1. The inner frame you're buying takes all the structural weight. The outer leaf is only cladding. You're correct in that lightweight cladding's will NOT carry conventional cills, etc.

2. There is an alternative to wool-filling the stud on the frame, which can be very hard to control the quality of..........unless you're standing beside the guy doing it............you can get the stud pumped with VPM applied inside. I've just done it to my new TF house.

3. You can have conc upstairs floors in a TF house. I have.

4. Aquapanel Exterior Cement Board System from www.greenspan.ie has an NSAI cert for durability of 60 years, with certain provisos. This is the longest 'guarantee' you can get on anything..........

frankie2shoes

thanks galwaytt,
have gone down the route of factory fitted 100mm solid kingspan insulation and have a strengthened upper floor to take underfloor heating/screed.
will look into the aquapanel cement board system