Latest site report from building regs inspector outlines the following:
1. Requested timber noggins to the first floor joists where sitting into joist hangers below the new first floor extension to prevent twisting of the joists.
What does this mean?
2. The trimmers to the two roof lights are not as shown on the architects design details. The larger roof light is shown to have four number timber trimmers either side and the smaller one is shown to have three. Only two trimmers have been provided around each roof light. Discussed this with the builder and he will rectify this.
What is the difference between a roof trimmer and a joist - is it simply one spans the full length of the room and a trimmer a shorter distance? Why are they called "trimmers"?
3. The pad stones provided under the steel beams to the rear wall have not been installed as per the architects design details. A single engineering brick has been provided. The design details indicate a dense concrete block. Advised that a dense concrete block should be provided as designed or three courses of engineering bricks installed to achieve the equivalent area of a block to spread the load onto the light weight block below. The builder will rectify this.
This seems a bit stupid for the builder not to follow the plans. Whilst the contractor indicated he will get this correct, in the scheme of things, how serious / big an error is this that he should have known better?
4. The external wall to the first floor rear extension has been built up to wall plate level. No cavity tray has been provided within the cavity masonry at the abutment with the flat roof. The builder is to remove the external skin and insulation and ensure that a cavity tray is installed which will be linked with the flashing to the flat roof. Weep holes are also to be provided above the tray.
We don't have a cavity tray or weep holes on the ground floor extension, so why the second floor? Could it be because we have solid concrete floors at ground level?
5. Discussed the existing first floor joists over the kitchen area. The ends of these joists have been notched considerably over the newly installed steel beams. It is understood that these beams will need to be replaced as their span is to be increased slightly due to the removal of an existing wall to the rear of the kitchen area. The span of these joists is approximately 4.5m. The replacement joists will need to be either 50mm x 200mm C24 grade timber or 75mm x 175mm C24 timber. At 400mm centres, both of these joist sizes are at their limit for a span of 4.5m and are acceptable however, it may be advisable to close up the centres of these joists to reduce any spring in the floor. Any notching of the joists should be kept to a minimum.
Is it not normal to notch out joists to fit into an RSJ? Also what is C26 grading and how do the C gradings work i.e what differentiates between the ranges?
How do they close up the centre of the joists?
6. There are areas of the external walls where brick work has been used in place of the light weight block work. Advised that the block work should be cut and block work used instead of brick work to minimise cold bridging. However, it is understood that the internal walls are to be dry lined with an insulated plasterboard therefore this will minimise the cold bridging issue.
Do light weight blocks have better thermal or insulation properties than bricks? How much better are they out of curiosity?
Is it normal for building inspectors to comment on remedial work for all builders, even good ones. Do they always find things to point out or do builders here go through extensions etc without any negative comments?
1. Requested timber noggins to the first floor joists where sitting into joist hangers below the new first floor extension to prevent twisting of the joists.
What does this mean?
2. The trimmers to the two roof lights are not as shown on the architects design details. The larger roof light is shown to have four number timber trimmers either side and the smaller one is shown to have three. Only two trimmers have been provided around each roof light. Discussed this with the builder and he will rectify this.
What is the difference between a roof trimmer and a joist - is it simply one spans the full length of the room and a trimmer a shorter distance? Why are they called "trimmers"?
3. The pad stones provided under the steel beams to the rear wall have not been installed as per the architects design details. A single engineering brick has been provided. The design details indicate a dense concrete block. Advised that a dense concrete block should be provided as designed or three courses of engineering bricks installed to achieve the equivalent area of a block to spread the load onto the light weight block below. The builder will rectify this.
This seems a bit stupid for the builder not to follow the plans. Whilst the contractor indicated he will get this correct, in the scheme of things, how serious / big an error is this that he should have known better?
4. The external wall to the first floor rear extension has been built up to wall plate level. No cavity tray has been provided within the cavity masonry at the abutment with the flat roof. The builder is to remove the external skin and insulation and ensure that a cavity tray is installed which will be linked with the flashing to the flat roof. Weep holes are also to be provided above the tray.
We don't have a cavity tray or weep holes on the ground floor extension, so why the second floor? Could it be because we have solid concrete floors at ground level?
5. Discussed the existing first floor joists over the kitchen area. The ends of these joists have been notched considerably over the newly installed steel beams. It is understood that these beams will need to be replaced as their span is to be increased slightly due to the removal of an existing wall to the rear of the kitchen area. The span of these joists is approximately 4.5m. The replacement joists will need to be either 50mm x 200mm C24 grade timber or 75mm x 175mm C24 timber. At 400mm centres, both of these joist sizes are at their limit for a span of 4.5m and are acceptable however, it may be advisable to close up the centres of these joists to reduce any spring in the floor. Any notching of the joists should be kept to a minimum.
Is it not normal to notch out joists to fit into an RSJ? Also what is C26 grading and how do the C gradings work i.e what differentiates between the ranges?
How do they close up the centre of the joists?
6. There are areas of the external walls where brick work has been used in place of the light weight block work. Advised that the block work should be cut and block work used instead of brick work to minimise cold bridging. However, it is understood that the internal walls are to be dry lined with an insulated plasterboard therefore this will minimise the cold bridging issue.
Do light weight blocks have better thermal or insulation properties than bricks? How much better are they out of curiosity?
Is it normal for building inspectors to comment on remedial work for all builders, even good ones. Do they always find things to point out or do builders here go through extensions etc without any negative comments?
