Underpinning

When the toilet was removed from the back of the house it was confirmed that there was no substantial foundation under the area of the door. This was to be expected as this was an internal wall, however, we need this to support the floor joists for the extension so a small underpin was required.

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This was the situation once the toilet walls and floor had been removed.

You can see there is only a floor slab under the remaining wall.

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A hole was dug under the edge of the floor slab to take the concrete for the foundation.

Whoever underpinned the house had placed a huge lump of concrete under the toilet floor, this was strange as we could see no reason for it having been placed there. You can see the top of it at the bottom of the picture.

This hole needed to be dug by hand as with the existing concrete and the wall there was not enough access to get the digger in.

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This angle gives a better idea of the depth of the hole.

It was taken down to 1.5 metres to match the other foundations we had put in and to get it below the level of the existing underpinning.

You can see the existing, but not actually doing anything, underpin on the left with the clayboard attached to the face of it.

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The hole then disappeared when it was filled with concrete.

A wall will be built up on this footing to hang the extension floor joists and also to take the end of the support beam for the current kitchen floor when that is replaced (hence why we wanted good support in that area).

The wall above will also be replaced as the door is no longer required in that position, but will stay for the time being.