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Hi All!
Sorry if this question has been asked before but I really need someone to break it down for me so that I can understand properly!
So I'm planning on building an outbuilding to house a gym in my garden. Unfortunately due to space constraints I have to build within 2m of the boundary and so the building can't exceed a height of 2.5m to be under permitted development. I applied for PP to have an increased height of 2.8m but unfortunately this was not approved so I'm struggling with what to do next.
I've been thinking of trying to sink the building into the ground a bit by about 30cm to give myself more headroom. I've spent time researching this and appreciate that this can cause damp issues which I've been trying to figure out how to mitigate. I dug a 1m deep
hole in my garden to check for the water table, when it rains there is about 10cm of water at the bottom of the hole, periodically checking this hole, I've not seen water any higher than this. When digging down to 1m I did not see any water filling up the hole immediately. I am on London clay if this makes a difference.
I plan to build the outbuilding on concrete raft foundation, with engineering bricks going from below the ground to 150mm above the outside ground level with a timber framed building sitting on top of this. There will be a step internally to climb down.
I've attached a plan for what I think will work as a foundation in this building while trying to avoid damp issues. The plan is to have the DPM come from under the raft foundation and up the outside of the bricks, with insulation between the DPM and brick wall. This will terminate and be lapped up to the DPC 150mm above the ground. I'm a keen DIYer but it's my first time building anything like this! Please do let me know if you think this will work or if there are any other ways you think are a more sensible way around this.
Sorry if this question has been asked before but I really need someone to break it down for me so that I can understand properly!
So I'm planning on building an outbuilding to house a gym in my garden. Unfortunately due to space constraints I have to build within 2m of the boundary and so the building can't exceed a height of 2.5m to be under permitted development. I applied for PP to have an increased height of 2.8m but unfortunately this was not approved so I'm struggling with what to do next.
I've been thinking of trying to sink the building into the ground a bit by about 30cm to give myself more headroom. I've spent time researching this and appreciate that this can cause damp issues which I've been trying to figure out how to mitigate. I dug a 1m deep
hole in my garden to check for the water table, when it rains there is about 10cm of water at the bottom of the hole, periodically checking this hole, I've not seen water any higher than this. When digging down to 1m I did not see any water filling up the hole immediately. I am on London clay if this makes a difference.
I plan to build the outbuilding on concrete raft foundation, with engineering bricks going from below the ground to 150mm above the outside ground level with a timber framed building sitting on top of this. There will be a step internally to climb down.
I've attached a plan for what I think will work as a foundation in this building while trying to avoid damp issues. The plan is to have the DPM come from under the raft foundation and up the outside of the bricks, with insulation between the DPM and brick wall. This will terminate and be lapped up to the DPC 150mm above the ground. I'm a keen DIYer but it's my first time building anything like this! Please do let me know if you think this will work or if there are any other ways you think are a more sensible way around this.
