Conservatory floor: solid v suspended

[Graham]

We have been given two contradictory opinions for the floor/base of a conservatory. One company says we need a suspended floor and that it would be 'ridiculous' to put in a solid concrete floor - because the height from ground to floor level is 85cm. The other says they never use wood because of expansion problems. The solid concrete floor would be insulated and both would have ducts in for airbricks on the side of the house.

Any opinions on which is better?

A second related question: should we have the floor flush with the inside of the house, and hence have more steps and a higher wall outside. Or would one step down into the conservatory be acceptable, allowing a lower wall and one fewer step outside - perhaps improving the external apperance?

Look forward to people's opinions. Obtained lots of useful information from this group's archives on roofs, glass, etc - realy helped in dealing with salesmen!

Graham

[Andy Hall]

Both work from the insulation point of view.

Wooden floors have been used in houses since time immemorial. Wood expands and contracts a little laterally but this is dealt with by the way the floor is fitted - assuming boards are used. If chipboard were used, there wouldn't be significant expansion and contraction anyway.

Both methods of construction are used, although the 850mm depth may impact on the choice because of the amount of fill required if a concrete floor is done.

I am not sure that I would make the decision based on the floor though.

One factor could be access. Are you planning to stay in the house a long time or have the possibility of an elderly relative staying with you, or a disabled person?

Depending on the house and surrounding ground layout, it may be preferable not to have a step between the house and conservatory.....

.andy

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[Rick Dipper]

Just to make the choices even more complex, you can have a suspended concrete beam and block floor. Check out the celcon website.

Personally I'd have a suspended floor, with a hatch in, & keep my wine down there. Now there is a dream, wine in the house thats not consumed within a day ......

Rick

[Andy Hall]

I know what you mean. I bought a wine box recently. It said on the box that it lasts for three months. It doesn't..... :-)

.andy

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[Rob Bradley]

information

I built a Wickes hardwood conservatory a couple of years ago with about the same height floor to ground as yours. I put in a suspended floor of braced joists, chipboard screwed down, Aquapanel screwed down, underfloor heating cable and finally tiles, and I haven't fallen through yet. It's important to have the floor as rigid as possible if tiling it, hence the braced joists, and of course a concrete floor, suspended or solid, would be rigid. My floor is at the same level as the house floor, with three steps down to the garden, and I admit the front wall does look quite large.

Rob

[N. Thornton]

.85m... you couldnt dig down to make that 1.85m could you? Could be kinda handy, free up your spare room etc.

you tell us, would it be acceptable for you?

The general rule of thumb is

1. try to avoid steps in floors, as theyre a real sod if you get real ill, and people do get real ill in old age.
2. but if ya have to have one to get things to fit, so be it.

I'd probably keep the floors level and dig down for another room beneath. The underground wont be seen from outside, so you can make it from poured concrete, concrete block, or whatever very low cost method you want. .85m gives you windows as well.

Regards, NT

[G&M]

Well we had over 25 feet of concrete (built on a marsh) below our last house so anything's possible.

But I would go for the suspended floor as well. Keep it flush with the house and use folding doors, not sliding patio doors so that the areas can become one.

[Sam]

A typical break point between suspended and ground bearing slabs is if the required fill is more or less than 600mm. How much topsoil/poor ground has to be removed will obviously affect this - with domestic building the ground pressures under a slab are low and so differential settlement w.r.t. the walls is the main criteria.

Both types of floor slab are fine - but as someone else said, if you use a suspended floor I would have a think about using a beam and block floor.

[Christian McArdle]

I've got a steel suspended floor in mine. 85cm would probably be too much for concrete. Although the steel floor is supposed to sit 20cm of so above ground pad foundation level, I've raised mine higher with dense concrete blocks.

Christian.

[IMM]

A masonry floor is cooler in summer as it absorbs heat. If you want to use the conservatory as a means of generating heat to fan into the main house then use as little masonry as possible in the construction. Dwarf walls and an insulated concrete floor are mush cooler in summer than a wooden floor with no dwarf walls.

[anthony.j.cunningham]

From the point of view of how it feels underfoot, a suspended floor beats the solid floor hands down. I've just had a conservatory built with a suspended floor and it's much nicer to walk on than my in-laws solid floor.