Building control site inspections

We see our inspection service as a key part in the success of your project, ensuring that the work your builder does complies with the regulations, and helping them with advice in that context.
Inspections are carried out at a number of stages during the building process. These are set out below with notes which may assist you or your builder. If we look at two examples, a kitchen extension and a loft conversion, you will see the typical inspections that may be required and why we need to inspect.
Kitchen extension or any typical extension to a dwelling
Commencement
This is usually for information only and will often be combined with the inspection for the excavations.
Excavations
This inspection is to ensure that the ground upon which the building is to be founded is satisfactory. The Building Control Surveyor will consider various aspects during this inspection, including:
- The load bearing capacity of the ground.
- The proximity and depth of any drains and manholes.
- Any indication of filled ground, (generally or limited areas).
- The depth of existing foundations.
- Proximity of trees or trees already removed
Damp proof course (DPC) and oversite
The main points will be:
- The suitability of any hardcore used.
- Sand blinding to protect the damp-proof membrane (DPM).
- Checking that the DPM is of the correct thickness.
- Checking that any joints are rolled or taped up.
- Checking that sufficient DPM is left turned up the walls to tie in with DPC (both new and existing).
- Checking that the floor insulation is laid with tight joints and turned up the edge of the slab.
This is an ideal time to also discuss with your builder the wall, roof (and floor if two storey) specifications to ensure that the superstructure will comply with the regulations. This is particularly important if a Building Notice has been used.
Underground drainage
A number of details including those listed below will be looked at on this inspection and the request should be submitted before the drains are backfilled.
- Suitability of layout used.
- Fall and line of drain.
- Material used for bed and surround.
- Access points.
Superstructure (walls, floors and roofs)
Checking that what was discussed at DPC stage has been built, including sizes of timbers, spacing’s, lateral restraint to walls/roofs, bracing and any other structural requirements.
Drainage test
An air or water test of all above and below ground drainage is required. It is helpful if the test can be set up and ready for the Building Control Surveyors’ visit. It is appreciated that this may cause difficulty when existing drains are affected. To assist you in this situation a timed appointment can generally be arranged.
Completion
This is the key inspection for which notification is most often forgotten.
A thorough inspection is carried out to check all is ok. If it isn’t, we will tell you what the outstanding issues are so you can rectify them with your builder.
Once the works have been rectified we will re-inspect and ‘sign off’ the project closing the file.
You will then be issued with a Completion Certificate for the project. This is an important document and should be kept in a safe place. Should you sell your property in the future the purchasers solicitor will ask to see a copy of this.
Loft conversion either to a bungalow or two storey house
Commencement
This is usually for information only but will also allow us to meet your builder and look at the general structural and fire safety arrangements. It may also be possible to combine this with an inspection of the existing foundations and structure.
Expose existing foundations and structure
There are systems on the market that will carry the loads to the outside walls. But if a more traditional design is used we may need to check that the existing structure can take the increased loads, particularly if some loads are carried by inside (partition) walls.
Structural framework
In the majority of loft conversions some input is usually required from a structural engineer. Their role is to design the structural support frame to show compliance with the regulations ensuring also that the builder can build it. We check the finished frame against any engineers’ details and confirm if. this is acceptable or not.
Insulation requirements
Checking that all floor and roof insulation is to regulations and fitted properly.
Fire safety
Checking that the required arrangements are in place to meet the minimum standards.
Completion
See kitchen extension notes above.
Last updated: 25 August 2009

