Site Drainage Essentials
Poor site drainage can lead to many problems in and around your home.
Inspect around your property, especially adjacent to the house. After rain, a walk over the entire area will help to identify any boggy or obviously wet areas.
Rain water run off can accumulate in pockets and be held, even on sloping sites and especially in clay based or impermeable soils.
Lack of slope and concrete edging to this garden causes water ponding against the house.
Water ponding under the house together with poor subfloor ventilation can lead to mould and rot attacking subfloor timbers.
Water ponding against foundations, especially in areas with clay soil profiles, can lead to cracking in brickwork and even to serious structural failures.
This can also lead to rising damp in floor slabs and brickwork which can cause serious damage to building elements as well as mould in the house that can be a serious health threat to the occupants.
I recently conducted a pre purchase inspection on a seven year old home for a client and I discovered that bottom plate of the exterior wall frames was severely damaged by wood rot caused by rising damp to the extent that I could place my fingers under the wall frame where it should have been solid timber.
Severe wet rot to the wall frame behind the wall sheeting.
Rising damp can cause damage to various building elements.
Moisture in and around houses is also very attractive to termites as they need moisture to survive, which is another very good reason to ensure proper drainage to all areas.
It is very important to ensure that water cannot enter the subfloor area or pond adjacent to the house. Provide suitable gradients to all hard and soft surfaces and where necessary install in ground pipes and drainage systems.