Firedoors

[PCAnimal]

Hi my builder is fitting firedoors and has given me a choice.
He said he could fit intumescent strips into a router gap on the doors or attach strips to frame. I'm getting oak composite firedoors
Im not sure which to choose.

 

[^woody^]

If this is for a lot conversion, the requirement is FD20, so no strips are required.

Otherwise consider:

fitting in the linings won't wreak the door edging if the doors need lots of reduction

but if these are existing linings the builder probably won't be routing them so fitting plant on strips which look crap

Proper fire door will have a certificate as this will state how it needs to be fitted.

Simple answer is routed into linings if possible.

 

[PCAnimal]

Thank you as always. The building control said all doors needed to be replaced onto stair enclosures. She said they needed 3 steel hinges and strips. I didn't want them but she said it's a must.
This is for a loft conversion

 

[JohnD]

Oak faced doors are presumably not cheap. New linings will give you a better job and are available pre-grooved.

So are you having new linings?

It's easier and looks better if you paint the linings before applying the strips. On a white surface they are not too ugly.

 

[PCAnimal]

Sadly no new liners. That's going to cause a huge disruption and cost a lot more I suspect.

Dare I say it! I was tempted to fit cheap ones get signed off and put my decent ones back. I've got interlinked smoke alarms in each room and the bedroom doors are left open... However we decided that was a lot of work and not ethical. The doors are around 100 each.

 

[^woody^]

Thank you as always. The building control said all doors needed to be replaced onto stair enclosures. She said they needed 3 steel hinges and strips. I didn't want them but she said it's a must.
This is for a loft conversion

She's wrong or at least misleading.

The requirement is for a "reasonable level of safety", and states that a FD20 doorset (door and lining) is needed - these have no strips.

It's difficult to buy a FD20 door nowadays, so it's generally accepted that a FD30 door (which would require strips) will perform as an FD20 door without strips fitted.

Hinges need to be steel, but not specific fire hinges. They are required to have a lower temperature rating of 800°, so normal 3" hinges of good quality will acheive this.

And it's only habitable rooms that require this.

Edit: normal linings will acheive FD20 standard.

 

[JohnD]

New linings are not a great upheaval. Architrave will cover the joint, but expect some redecoration afterwards.

The carpenter will grumble that the old linings are not square and blame them for any poor fit.

 

[tony1851]

If you have fire doors, and an alarm/detector on each landing of the staircase enclosure, you do not need intumescent strips.

The logic is that most fires at night occur downstairs in the lounge/kitchen areas. If the doors to those are closed at night and have intumescent seals, a fire could take hold before people sleeping upstairs become aware of it because smoke does not get into the staircase enclosure to set the alarms off. By the time it gets through a closed full 30 min door, it might be too late for occupants to escape - it could have weakened the floor above.

Many inspectors allow you to dispense with fire doors IF you have interlinked alarms/detectors in each habitable room as well as the staircase enclosure.

For HMOs, such as student houses, full 30 minute doors with self closers and seals are mandatory because the occupation of the house differs from an ordinary single-family house.

 

[noseall]

New linings are not a great upheaval

Depends upon the existing fitting gap. FD linings are thicker/wider overall. Can be a right pain widening a masonry opening by a small amount.

 

[PCAnimal]

I've got interlinked alarms in Every room. However the building inspector says they don't comply with the regs.

They say I need a control panel etc etc. I challenged this to get no where. They would accept a fire engineer report saying its fine. However I have no idea who to go to for that or how much it would cost.

Fire-engineered approach
In certain circumstances it may be possible to provide a
comprehensive fire alarm and detection system rather than
providing a protected stair (Solution 1 above) or an alternative
escape route (Solution 3). It should be appreciated that ‘a
comprehensive fire alarm and detection system’ is either a
Grade A or B system of a type described in BS5839-6 and
BS 5839-1 as appropriate (see Option 4 7.3.26/31 CPA Loft
Conversion Project Guide 2010). A number of factors must be
taken into consideration with regard to choice of system and
its design as well as the coverage required (i.e. LD1 /LD2).
These include:
• The probability of fire occurring
• The probability of injury or death of occupants if fire occurs
• The probability of the system operating correctly in the event
of fire
• The probability of early detection and warning of occupants
in the event of fire
• Any potential weakness in the integrity of stair enclosures
and doors onto stairways.
It is considered fundamental to the success of this solution that
any openings onto the stairwell from rooms and cupboards
should be fitted with doors. Whilst these doors do not need to
achieve the full FD20 fire resistance, they must be well fitting in
their frames, a maximum of 4mm gap at the head and side is
considered acceptable. Similarly, whilst the physical integrity of
the stair enclosure must be maintained, there is no requirement
to ensure the full 30-minute fire-resistant standard is achieved.
In all cases where this solution is proposed, it is recommended
building control should request that a report from a suitably qualified
fire engineer supports any scheme submitted under Option 4.
My existing doors are well fitted with no large gaps. It seems a real shame to rip them out.

 

[^woody^]

It's quite simple. The requirement is for a

Grade D system (interconnected detectors no panel)
to LD3 standard (detectors on escape routes only)
or depending on a more compext layout
to LD2 standard (detectors on escape outes plus high risk rooms)

That's what BS 5839-6 says, and Part B1 Building regs says to install in accordance with BS 5839-6 ....... so no fire engineer required.