ALERT | New standards for fire safety in dwelling houses 

21 March 2017

New standards for fire safety in dwelling houses have been published by the Department of Housing, Planning and Local Government

In general, this document applies to works to dwelling houses, or buildings in which a material change of use takes place, where the works or the change of use commence or takes place, as the case may be on or after 1 July 2017. The guidance given in Technical Guidance Document B – Fire Safety, dated 2006 relating to dwelling houses, will cease to have effect from that date. However, the latter document may continue to be used in the case of works, or buildings in which a material change of use takes place, where the works, material alteration or the change of use commence or takes place, as the case may be, on or before 30 June 2017

2 thoughts on “ALERT | New standards for fire safety in dwelling houses 

  1. Brendan Thomas

    Perhaps there is something in this reg. about control of the work on site, regulatory inspection etc. but I strongly doubt it. In that case it is practically useless in bringing in ‘beefed up’ measures if the system of certification of work remains unchanged – impractical and expensive.

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  2. Michael O'Neill

    I refer to: –

    ALERT | New standards for fire safety in dwelling houses

    http://www.bregsforum.com/2017/03/21/alert-new-standards-for-fire-safety-in-dwelling-houses/

    There are potentially fatal provisions in this Technical Guidance Document (TGD).
    This is because this TGD allows timber studs to be used as Party/ Separating Walls.

    Walls are massive elements of construction made of masonry. They are by definition incombustible.
    Timber Studs are lightweight elements made of timber frames. They are by definition combustible.

    These definitions are fudged if you sheath the frames in incombustible substances. Yet unless the timber stud is constructed to a very high standard it will not offer the claimed fire resistance or anything like it.

    Let us be clear. A timber stud is not a wall. There is a wide difference in performance between: –

    (i) incombustible 215mm concrete block walls with full bed and perpend joints plastered both sides, and
    (ii) badly built combustible timber studs with services – including electrical services – in them.

    A 215mm solid block wall can give over 2 hours fire resistance. Badly built timber studs may give less than 4 minutes fire resistance.

    The rate at which fire spread through six terraced houses in Millfield Manor suggested that their timber frame Party/Separating “Walls” may have been constructed with: –

    – inadequate build-up of incombustible coverings ( perhaps only 1 layer of plasterboard)
    – inadequate support for those coverings (no robust framing extended up to the roof)
    – inadequate sealing of the stud (no top frame member)
    – inadequate fire sealing to the underside of the roof” (no fireproof compressible material ) and
    – timber battens across the top of the Party/Separating “walls

    See http://www.irishexaminer.com/viewpoints/columnists/michael-clifford/kildare-fire-safety-concerns-arise-from-celtic-tiger-ashes-321931.html

    Other recent building failures and the discovery of extensive remedial works required to many non-compliant buildings show that Irish Builders do not seem to understand timber stud construction or how to fire-proof it. Calling timber studs “walls” in this context is grossly misleading and may have fatal consequences.

    This TGD allows masonry and timber Party/ Separating Walls to be crossed by continuous timber battens. Fire can spread interstitially, without breaching the roof membrane of class AA, AB or AC materials. Continuous timber battens can allow fire to spread between the attic spaces of dwellings. The writers of this TGD do not seem to understand how fire propagates from one semi-detached /terraced house to another.

    This TGD allows electrical services to be routed through combustible timber framed Party/Separating walls, creating potentially fatal risks for owner/occupiers of dwellings. The irony is that this TGD does not allow electrical services to be routed through incombustible masonry walls. This is a wise provision. Badly installed electrical installations can be a source of fire.

    Given the state of drywall construction, suggesting these services will run within party walls “external” to what is euphemistically called the “unbreached linings of the fire resistant separating wall” gives no assurance.

    This TGD, by allowing timber studs to be used as Party / Separating Walls, does not serve us well.

    = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

    (Extract from 3.5.4.3 Separating walls in timber framed construction)

    An exception to the requirement for separating walls to be constructed of noncombustible materials may be permitted in the case of separating walls in timber frame dwelling houses built in accordance with I.S.440:Timber Framed Dwellings; between buildings of up to three storeys, (four storeys where the provisions of section 1.3.4(vi) are complied with) where the design, materials and workmanship used in the manufacture and construction of the wall are in accordance with the provisions of Technical Guidance Document D (Materials and Workmanship)

    (Extract from 3.5.4.4 Services in separating walls)

    No services should pass through or breach separating walls. In timber framed construction, where necessary, a service cavity external to the unbreached linings of the fire resistant separating wall should be provided to accommodate services as outlined in IS 440.

    (Section 3.5.4.6 Junction of separating wall and roof)

    The junction between a separating wall and the roof of a building should be capable of restricting fire spread between the buildings.

    A separating wall should be taken up to meet the underside of the roof covering or deck and fire stopped where necessary at the wall/roof junction.

    The construction of the wall, particularly between any ceiling and the roof, should not contain imperfections that would provide a route for fire penetration or premature failure of the fire resistance performance of the wall.

    The gap between the wall and the underside of the roof should be as small as practicable (generally not greater than 50 mm) and be filled with suitable fire stopping material over the full width of the wall.

    Where structural roof members such as beams, purlins and rafters are built into a separating wall, any openings for them should be as small as practicable and any gaps should be effectively fire stopped with non-combustible fire stopping material over the full width of the wall.

    No structural roof member should be carried across a separating wall.(except where specified at (a) below)

    The design and detailing of the junction between a separating wall and any roof valley, gutter, or other roof configuration, should be carefully considered so as to ensure that a means is not provided at the junction for premature fire spread between compartments or buildings.

    If a fire penetrates a roof near a separating wall there is a risk that it will spread over the roof to the adjoining building. To reduce that risk, the junction between a separating wall and a roof should be constructed in accordance with the following:

    (a) In dwelling houses not more than 15m high a zone of the roof at least 1.5m wide (see Table 4.3)on both sides of the wall should have a covering of class BRoof(t4) (European class) or AA, AB, or AC (National class) (see table A4 to Appendix A).

    Where timber tiling battens or combustible boarding used as a substrate to the roof covering, are to be carried over the separating wall, they should be fully bedded in mortar or other suitable non-combustible fire stopping material for the full width of the wall.

    Boarding should not exceed 25 mm in thickness, and any cavities within the thickness of the roof, above and below the sarking felt or similar membrane along the line of the wall and at the eaves should be adequately fire stopped (see Diagram 10(a)).

    (b) As an alternative to (a) above the separating wall may be extended above the line of the external roof surface by a height of not less than 375 mm to form a parapet wall (see Diagram 10(b)).

    (c) As an alternative to (a) or (b) above, any other system which has been shown by test to be equally effective in restricting the spread of fire at a separating wall/compartment wall/roof junction may be used.

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