Conservatory (In costing stage)

Postby Paul-E » Sat Apr 26, 2008 3:43 pm


I'm currently costing a diy conservatory before deciding on go ahead.

The problem I have is that the ground level between the house floor level and outside patio level is a 500mm drop. Other problems I have which would be rectified by raising outside floor level (which I will ask about later) is a large patio door already in place (which will give access to conservatory) plus a boiler flue (which cannot be moved) and also a flat roof!

The conservatory planners have taken all this into account and come up with a size and type (hip with boxed gutter) that will overcome these issues. However that leaves one problem for me..................the ouside ground level needs raising:-

My question would be this:

The patio already in place (500mm below building floor level) has concrete base to a depth of 400mm onto clay. Can the patio slabs be removed and the base for the conservatory be built up from the original patio base? Or do I need to dig through patio base down to clay and add new footings for conservatory?

Any help appreciated. Been researching for two days now, still none the wiser. I've spoke to two builders one saying it would be ok to build up from current patio base but another saying to dig out new footings......what to do?

BTW Conservatory would be dwarf walled 4000 x 4975 with glass roof.

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Simply Build It

Postby welsh brickie » Sat Apr 26, 2008 8:05 pm

you must check with planning office before starting any works.
But if you already have and agreed the go ahead,you must dig out for a
concrete foundation ,the depth depends on ground conditions but I would
recommend at least 600mm with 225mm concrete foundation.
welsh brickie
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Joined: Sat Apr 12, 2008 7:54 am

Postby Paul-E » Sun Apr 27, 2008 4:08 pm

Thanks Brickie

So I will have to dig away patio base and do new foundations at depth of 600mm (depending on ground conditions). When you say concrete foundations at 225mm Is that the thickness of concrete poured into 600mm foundation?

We haven't ordered or agreed to anything as yet.

I'm going in to see planning next week with plans of intended cosevatory to sort that side out and make sure everything is ok because my neighbour is a ppain in the neck so everything needs to be spot on. It is just these foundations I need to cost. I've costed everything above ground with a contingency.


Welsh Brickie
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Postby welsh brickie » Mon Apr 28, 2008 2:39 pm

yes 225mm thick concrete
Please make sure you get exact dimensions of your base and build to
exact measurment other wise the roof wont work.
welsh brickie
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Postby Paul-E » Tue Apr 29, 2008 7:36 pm

Thanks Welshbrickie. Will do.
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Postby TheDoctor4 » Tue Jul 27, 2010 9:12 pm

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