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After 4-5 weeks of cajoling our BC provider has final got back to us, for the second time with many of the same issues from the first time, despite me pointing out that they had all the answers, bar one on day 1. One is wondering if they read the stuff you send them. Here is what our BC wrote. "I have check through this package of drawings, and we still seem to be missing the following details. 1. Please provide details of the fire resistance to external walls within 1.0m of the boundary. This should be in terms of its minutes of fire resistance from inside and outside. 2. Please provide design specification for the proposed MVHR ventilation system. We have a layout but need the design details. 3. Please confirm the provision of network access to the new dwellings. 4. Please provide design details for the proposed staircase, and guarding to low level glazing. 5. As an extra item I picked up, please can you confirm that Bedroom 3 will have an escape window as it is an inner room." Here are the portions of our documentation that applies, and I admit that I assumed that when you gave BC a fire rated class EG AA they could work out that it is 1 hour, and that is just the outer cladding. 1. The architects drawings, see above, refer to details under these headings as do the structural drawings and calculations in terms of charring. External walls within 1000mm of a boundary. The external walls are clad with fire cement tiles in line with the architects specification the tile specification will be as Marley Thrutone and these are rated CLASS 0 as is required within 1000mm of a boundary. Details can be found in the properties and performance page of THIS (hyper link) document from Marley. 2. To comply with BR Part F1 Section 5 A whole house MVHR system will be installed to provide ventilation in excess of the minimum required. Flow rates will be verified during commissioning of the MVHR system. Details of pipe runs and locations of Plenums are shown on the architect’s drawings but may alter slightly as the build progresses alongside the development of MVHR technology in the wider sphere. All the Extracts from WC, Bath rooms and Kitchen area will be sized to exceed the requirements of Part F Section 5 – Table 5.1a and whole dwelling ventilation Part F Section 5 – Table 5.1b against the 3 bedroom dwelling criteria. The Kitchen Cooker hood will be a carbon filtered recalculating unit. In addition to the MVHR system and to support summer cooling a passive stack circulation system has been designed into the build using the electrically controlled high level opening roof lights. - AND IN THE SAP CALCULATIONS SECTION - (Full MVHR System – unit TBA, but probably the Airflow Adroit DV145 but Efficiency of at least 90%) 3. The building is connected to the main telephone and ADSL network via the utilities building, adjacent to the telegraph / power pole in the front garden, and is then ducted into the main house from the utilities building. 4. A final design for the stair case is not yet complete but it will be so designed as to meet the requirements of BR Part K. (I admit I did not specify guarding of low level glazing but the architects specification refers to toughened glass everywhere.) 5. Means of Escape: All habitable stairs connect directly to the main entrance area and external doorway. Both first floor bedrooms will have clear openings that meet the acceptable dimensions in BR Part B section 2.8. The ground floor bedroom (Bedroom 3) will also have a clear opening that meets the acceptable dimensions in BR Part B section 2.8. What have I got wrong? I could tighten up 1 and work out the delay times both ways and that I will do. Do they want air flows, volumes etc for all the rooms and spaces in 2. Not sure I can be clearer in 3 (The drawings do show the duct). 4. Seems acceptable to me but maybe I have to complete the design before they will sign off the plans. 5. I don't think I could be clearer. Calm me down someone or tell me I am wrong, in which case I will open my second beer and do it all again.

I've been asked to try and help someone out who lives in a nine storey building, that has been clad in a similar way to Grenfell Tower. The residents have had some advice and have now fitted a linked alarm system, and changed the "action in the event of fire instructions" from stay put with the doors closed, to evacuate, with an evacuation plan. They are now looking for a Chartered Fire Engineer who is prepared to evaluate the fire risk from their cladding system and come up with the best way to make their building comply with both the building regulations and the requirements of the local fire officer. Just to avoid this thread getting derailed, the cladding and insulation was applied before the last change to the building regs, was probably compliant at the time it was fitted (over ten years ago), and the building is privately owned and occupied. The legal situation with regard to the cladding and compliance with Part B is still an ongoing issue, I believe, but the residents primary concern is to find someone who can act for them in coming up with a plan to help them make their building safe. The chap I'm trying to help is chairman of the residents management organisation, and also a resident. The building was built new in 2004/5 (so just out of the NHBC warranty period) and currently they have been advised by building control and the fire and rescue service that their initial mitigation action makes the building safe enough to live in for now. The cladding is the same as that on Grenfell Tower, but was fitted when the building was constructed. A personal recommendation for a suitable Chartered Fire Engineer would be preferred over just choosing one at random.