Expert Advice Intumescent & Fire Proof Paints

Date Published:

26/06/2009

Can you upgrade old Victorian doors with intumescent paint or should you be using fire doors, too?

Fire Doors

If the doors in the house you're renovating are really past it, it's going to be better to replace them with fire doors, assuming that's what's required by building control. Be aware that there are different finishes available - those with a wood grain effect look pretty obviously like fake wood, while those with a smoother finish, will look brand new (as opposed to the aged, bashed about charm of older period doors), but are not so self-consciously trying to mimic period doors.

As for installing a fire door, it's worth knowing that, even with the correct components, it could be useless unless installed correctly. The installation instructions, which must be followed to maintain the door's certification, outline the permitted gaps between door and frame, what size and material the frame should be made from, how to attach the frame to the wall and the components required, and any trimming allowance for the door.

Installation is the final stage of the certification process and is more than just hanging a door; it is a specialist task. If the door is wrongly installed, smoke and hot gases can easily travel through the gaps, and it may only provide a fraction of its expected resistance.

Upgrading Existing & Period Doors

You can buy intumescent door upgrade kits to fire door standard FD30 from companies such as Envirograf.

'There are many types of timber doors,' says Gary Bryant. 'They normally fall into two categories: solid timber doors (these doors are constructed of solid sections of timber all the same thickness then joined together and are sometimes these are called ledge & brace doors); and panel doors, which will have a frame made from solid timber normally 34-45mm thick and then have inset panels. There can from two to eight panels, and of course varying sizes. The classic is what I call the four or six panel Victorian style door. These doors' thicknesses range from 34mm to 45mm with panel size thicknesses of 6-12mm.'

'When upgrading these doors you have to use two materials: a special paper over the panels and a paint system on the beading rails & styles (vertical & horizontal sections of the door) the application is as follows:

'Start by applying the paper to each panel face with a special supplied adhesive, the paper is 1.2mm thick and is easy to cut. Apply the adhesive to both the panel and the paper, bring them together and, with a decorator's seam roller, roller all the adhesive out around the edges, wiping away the excess onto your next panel. Complete all the panels on the door and allow to dry for 24 hours. Then, apply an intumescent paint system which comprises a primer, a base coat and a top sealer coat. This is applied to the beading rails & styles of the door if they are between 31-35mm thick. If the doors are 36mm or thicker the paint system only needs to be applied to the beading around each panel.'

Buying The Right Paint

There's an array of suppliers for intumescent and fire proof paints - and finishes range from white matt, gloss and satin to clear. But which is suitable for you?

'I can only speak for our company, but we give the third degree to all our customers before selling them products. If things go wrong, it is normally because we've been given incorrect information,' says Gary. 'As for selling these paints for doors, we always ask the same questions:

* What is the thickness of the edge of your door?
* Are your panels uniform thickness panels or raised & fielded panels?
* What is the thickness of the panel (to work that out, take a straight edge across the panel, measure the depth with a ruler, how far the panel goes in from the underside of the straight edge, double that figure and then subtract it from the thickness of the edge of the door)?
* What's required, FD20 or 30?
* Are your doors painted or natural timber?

Once we have the answers to the questions we can tell them the correct system to use.'

For More Information & Suppliers

For More Information
To upgrade an existing door to a fire door with a kit costs from around £30.
Clear intumescent varnish costs from around £21 per litre; the paint is £17 per litre.

Association for Specialist Fire Protection
Passive Fire Protection Federation
British Woodworking Federation

The Fire Protection Association and the Association of British Insures publish a document, available as a free download, called The LPC Design Guide for the Fire Protection of Buildings and this will give you guidance with regard to increasing the level of passive fire protection in your building.

Go to the government's website for Part E Fire Safety of the Building Regulations (Northern Ireland) 2000 to see how compliance may be achieved.

Technical Standards for fire performance of buildings are available from the =Scottish Building Standards Agency.

Details on Scottish fire safety legislation is available from www.infoscotland.com/firelaw.

Where To Buy
Envirograf