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Windows diary
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Demolition diary
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Foundations diary
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 Drain issues
 Digging the foundations
 Rethinking foundations!
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Floor slab diary
 Rethinking the slab!
 Floor vent extensions
 Preparing the slab #1
 Preparing the slab #2
 Pouring the slab

Walls diary
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 Build the walls #2
 The gas men cometh
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Roof diary
 Roof structure build
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Internals
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Project finished!
 Final inspection
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 Twelve months on!
Out-takes!
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Costs
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Links
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Sister sites
 House re-roof project
 Home gas usage data

 Stop paint flaking
 DIY secondary glazing
 gare.co.uk

 


Possible sewer drainage issues
 
 

As mentioned earlier, the main issue that will determine the level of the floor inside of the extension is the current level of the main house sewer drainage pipe and the level of the inspection manhole (Drain #2 below). I want to remove the two steps up to the back door so that the level of the floor is as indicated.

This will cut a slice off the top of the inspection chamber. If the distance between the between the top of the drainage pipe as it enters drain #2 inspection chamber and the proposed floor level is too little the main drainage pipe might have to be lowered or the floor raised.

Showing the position of the drainage inspection chambers (accurate scale)

Showing the main drainage pipe looking underground (accurate scale)

Fortunately it looks like the distance from the floor level to the top of the drainage pipe is around 30 cms (12") so there is still plenty of height in the inspection chamber. Hopefully, the proposed level of the floor in relation to the drainage pipe is fine.

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