1. Do you manufacture insulations that can be used in my loft conversion for the walls and floor?2. How can a common loft area be split up to achieve the 60-minute compartmentation requirement between dwellings?3. Where do I place the vapour control layer (VCL)? 4. What is a cold bridge5. How can the gaps between the head of a block work wall and a tiled or slated pitched roof be sealed to prevent fire spread to the adjacent property?6. If I fully fill my masonry cavity wall with Rockwool Cavity (full fill) Batts, will I require additional fire stopping at the party wall junction? 7. How can I prevent fire entering a cavity wall around window and door openings and subsequently spreading throughout the building envelope?8. When installing recessed lighting within a ceiling are there any precautions required if there is already insulation between the joists?
1. Do you manufacture insulations that can be used in my loft conversion for the walls and floor?
Yes we manufacture a product called Rockwool Flexi, this can be used in either wall or floor applications, i.e. to achieve the thermal regulations of 0.35w/mk in a wall you will require 120mm Rockwool flexi. Whereas in a floor situation will 100mm Rockwool Flexi supported on a 25mm wire mesh a lath and plaster ceiling (in good repair) and a t&g floor board above you will give the necessary fire resistance. This will also give you the acoustic requirement as required under acoustic regulations in TGDE.
2. How can a common loft area be split up to achieve the 60-minute compartmentation requirement between dwellings?
Two layers of Rockwool Fire Barriers suspended from the soffit will satisfy this requirement. The Barriers should be installed in accordance with the product data sheet using the proprietary fixings, and also sealed to the head of the compartment wall to maintain the integrity of the entire system.
3. Where do I place the vapour control layer (VCL)?
Always place the VCL on the warm side of the insulation. This controls the vapour escaping out into the construction.
4. What is a cold bridge
A cold bridge is when the insulation is missing in the insulating layer, or it there are “gaps” where the insulation is not butted tight together or to the adjoining structure.
5. How can the gaps between the head of a block work wall and a tiled or slated pitched roof be sealed to prevent fire spread to the adjacent property?
There are two paths which require sealing to maintain the fire compartmentation at this junction – between the masonry wall and the underside of the roofing felt and within the timber batten void, between the felt and the tiles/slates. 300mm wide strips of 30mm thick Rockwool RWA45 can be used in both instances. Provided the masonry wall width is at least 250mm and the insulation is inserted under at least 10% compression, the 60-minute requirement of Building Regulations will be met.
6. If I fully fill my masonry cavity wall with Rockwool Cavity (full fill) Batts, will I require additional fire stopping at the party wall junction?
No – In the opinion of the Irish Agrément Board , Rockwool Cavity will satisfy the following requirements of the TGD to Part B, Building Regulations:
Resistance to fire spread between and within cavities. Rockwool Cavity is non-combustible and therefore may be used in buildings of every purpose group.
They may also be considered as a cavity barrier when tightly fitted between masonry leaves where an insulated wall connects with the cavity of a wall without cavity insulation.
7. How can I prevent fire entering a cavity wall around window and door openings and subsequently spreading throughout the building envelope?
Rockwool fire rated cavity closers, Rocklose and RockReveal are designed to provide a tight, fire resistant seal in a masonry cavity around window or door openings. Rocklose is a first fix solution which is similar but narrower product to Rockwool Acoustic Party Wall dpc. RockReveal is a second fix solution which does not need additional dpc. Both products will achieve 30 minutes fire resistance and also meet the TGD L requirement for minimising cold bridging.
8. When installing recessed lighting within a ceiling are there any precautions required if there is already insulation between the joists?
Never cover any light fitting which penetrates the ceiling such as recessed spotlights and downlighters with insulation; otherwise serious overheating may occur! Keep insulation 75mm away from recessed lighting.
Fit a light guard
A physical guard is required to keep recessed light fittings free from insulation.
