trada tables say that 8x2 is just about OK. whats the roof currently made out of?
Your other issue is that 10 degrees is into flat roof territory. There aren't many slates or tiles that work at such low pitches.
There shouldn't be any inherent bounce in the sub floor, it's block and beam, but the OP wants to introduce some insulation self adhesive underlays such as elastilon can be excellent. I have laid several floors on it. It is a great compromise between a floating and glued down floor.
Personally...
what linseed oil have you used if it isn't boiled it will never really dry out, just soak in
I would never use it for a floor it will just pick up dust and dirt for ever and a day. It will also seriously discolour and yellow over time. It also has very poor waterproofing properties.
Boiled...
Not really, what is the pitch of the roof, even 8x2s are really underspeced for 4.5m span even at a 30-45 degree pitch.
More importantly you say it's a conservatory, is the actual structure capable of taking the extra weight of the rafters and roof
I think that judging by the top fixing arrangement you can be pretty sure it is a Sandtoft, I would concentrate your search there. My guess is it's a fore runner of the Rivius which isn't made anymore. You might be just as well contacting Wienerberger
VCL nailed to the deck then sealed with bitumen, then the insulation which has ply top deck fixed to all that.
so order from bottom up.
joists
furring pieces
ply sub deck
VCL
bitumen
insulation with bonded ply top deck
roof covering
that's a lot of ****ing around, back in the day. First day on site, cut a pallets down to 2/3 their size and screw them together at an angle with a bit of bracing to form an A frame not the lightest I will grant you but took about 10 min s to make a pair. Throw them on the fire on your way off site
can't remember the last time I got the router table out. Normally knock one up when I need one from a bit of ply or MDF. Cut a hole in it, screw the router to it, make a fence up out of a bit of batten and sling it across two saw horses
ha ha fair enough each to their own, I suppose I've never known anything else.
Seriously though I ain't going to spend 250 quid on a hammer I would want it to bang the nails in on it's own for that sort of money.
Be assured they don't. I have a wall cupboard with a 12 setting dinner service and other stuff in and its been there for 15 years now
Once you have levelled your cupboard you tighten the brackets to pull them in tight unless you are planning a wrestling match you won't knock them off. The world...