I've built a posh garden office. It will be used for office-ing and occasional sofa-bed guest room. Its under permitted development and so far no building regs or planning permission involved. (<2.5m high, <15 sqm, <1 m from boundary wall).
It will feature a small sink and toilet (saniflo compact) which will pump the waste ~15 m back to the house via 40 mm waste pipe (1/40 fall, AAV at highest point).
My problem is getting the fresh water from house to new building. I can tap off a washing machine supply in the garage, but the pipe needs to get past an area of decking over concrete, a raised concrete patio, and a recently installed gravel area. Frost protection is my main concern. The pipe will be in regular use most days for a small amount of water, but we could go away from home for a couple of weeks in which case it will be unprotected and water will be static.
View attachment 340644
View attachment 340645
Here is my plan.
The pipe exits the garage wall and is laid on top of the concrete slab/under the decking, insulated and mechanically protected (SHalloduct or similar).
The decking will be extended to meet the concrete patio slab so the pipe will be covered up to the patio.
Then the pipe is buried 300 mm deep under the concrete raised patio and gravel area - still in SHalloduct.
The pipe then travels along the back of the new building (as it enters the building at the far back corner). It will be buried around 100 mm deep and right up against the insulated concrete slab foundation. I'm not worried about frost protection here. The concrete slab will be acting as a thermal battery/storage heater for the building. The insulation is only 25 mm thick around the sides, so this will keep the adjacent ground temperature stable even over a prolonged period.
The pipe will then pop up out of the ground where it enters the building, this short section will be Insuduct or my own sketchy DIY imitation made from EPS insulation and treated exterior ply.
Considerations:
Will the SHalloduct solution be adequate protection laid over the concrete slab under decking? Will it be enough buried shallow in the concrete raised patio?
Do I need to add trace heating at least for the under-decking section?
Am I overthinking it?
It will feature a small sink and toilet (saniflo compact) which will pump the waste ~15 m back to the house via 40 mm waste pipe (1/40 fall, AAV at highest point).
My problem is getting the fresh water from house to new building. I can tap off a washing machine supply in the garage, but the pipe needs to get past an area of decking over concrete, a raised concrete patio, and a recently installed gravel area. Frost protection is my main concern. The pipe will be in regular use most days for a small amount of water, but we could go away from home for a couple of weeks in which case it will be unprotected and water will be static.
View attachment 340644
View attachment 340645
Here is my plan.
The pipe exits the garage wall and is laid on top of the concrete slab/under the decking, insulated and mechanically protected (SHalloduct or similar).
The decking will be extended to meet the concrete patio slab so the pipe will be covered up to the patio.
Then the pipe is buried 300 mm deep under the concrete raised patio and gravel area - still in SHalloduct.
The pipe then travels along the back of the new building (as it enters the building at the far back corner). It will be buried around 100 mm deep and right up against the insulated concrete slab foundation. I'm not worried about frost protection here. The concrete slab will be acting as a thermal battery/storage heater for the building. The insulation is only 25 mm thick around the sides, so this will keep the adjacent ground temperature stable even over a prolonged period.
The pipe will then pop up out of the ground where it enters the building, this short section will be Insuduct or my own sketchy DIY imitation made from EPS insulation and treated exterior ply.
Considerations:
Will the SHalloduct solution be adequate protection laid over the concrete slab under decking? Will it be enough buried shallow in the concrete raised patio?
Do I need to add trace heating at least for the under-decking section?
Am I overthinking it?
