Timber Fascia for Iron Girder/joist

[dishman]

Hello,

I have a old Iron Girder/joist wich acts as the support for the opening in a 1930s garage.

It has an existing timber fascia which was badly fitted and is rotten in areas. This was not original but was fitted when the garaged door was replaced with a metal up and over. The timber frame for the garage door was poorly fitted too.

As I am now replacing the garage door I am also replacing the fascia.

After taking off the existing one I can see that whoever fitted it before wedged in chocks at regular intervals along the I shape of the girder. However the chocks were too deep and hence the fascia protruded or sat proud too much.

Looking at my neighbours garage which has the original fascia I can see it is flush up to the girder. I cannot see any nail heads (maybe hidden under layers of paint). There are no other types of fixings visible.

Is the chock method the best way of attaching the fascia? I am just trying to work out how it was originally fitted.

 

[Deleted member 174758]

Those "chocks" you refer to are normally called soldiers by chippies round here and unless you have access to a concrete nailer they are pretty much the only way to provide grounds to fix cladding onto. They need to be slightly tapered to get a good wedged fix and if installed correctly they should sit flush with the edge of the RSJ (rolled steel joist) - so yours were probably badly installed. Yes, you do nail or screw the ckadding onto them. For exterior use I'd recommend using tantalised ("treated") softwood

 

[foxhole]

If you use pvc facia you can glue it on, or screw a timber baton to the underside of the steel to allow fixing.

 

[dishman]

Soldiers it is then. I also managed to find a youtube video of someone boxing in an rsj using the same method.

The soldiers in there at the moment are tapered as the iron girder also tapers in a bit too. As you say they were just badly sized and were too deep resulting in fascia standing proud which made it more susceptible to rain getting in and rotting it from behind.

I am not a fan of pvc fascia but aware it was an options, thanks for suggesting it as an option.

Is there a rule to tapering the soldiers? The girder also tapers. So do I just measure the maximum height of the space for the soldiers and cut them to that size and then hammer like a madman so they wedge themselves?

 

[Deleted member 174758]

Is there a rule to tapering the soldiers? The girder also tapers. So do I just measure the maximum height of the space for the soldiers and cut them to that size and then hammer like a madman so they wedge themselves?

Not really. A couple of degrees on either side is generally enough. Measure the width between the joist edges, add a millimtre or two, cut, then bang in (I use a club hammer - the extra weight makes for a case of "resistance is futile"). If they are too loose they'll be no good, if they are too tight they'll sit proud - it's really a suck it and see approach, even for the pros

 

[foxhole]

You could drill the steel and fix a timber.

 

[dishman]

There are actually two large bolt holes at either end of the of the 218cm girder. I may actually use these, but I doubt they will hold the hole fascia tight in place for the whole length. I think the soldier method is easy enough.

 

[dishman]

Oh, one furthwer question. The existing fascia was nailed to the soldiers using lost head nails. I assume to make the nails invisible once painted. Is this still the best method for a clean fascia look. I assume the alternative is more visible screws? Is there a specific screw type for external fence work?

 

[dishman]

On knocking out the old poorly sized soldiers I found another large coach bolt hole in the middle. Would three bolts hold a 284mm span? Or should I go with the soldiers?

 

[Deleted member 174758]

Lost head nails? With softwood I'd simply have used small ovals, punched them under then filled with a 2-pack wood filler, sanded when cured (30 minutes to an hour). For screws I'd drill and countersink (so the heads will be below the surface) then fix with countersunk screws and fill as before - for exterior BZP (bright zinc plated) screws are generally OK, but if you are concerned about weather penetrating and causing rust you could always go for phosphated decking screws (generally green or brown) or even stainless steel screws. And yes, I'd still use soldiers. Fascia material is often quite thin and any attempt to bolt through it whould mean using something like coach bolts which are rather obvious. I'd also prefer a few more than 3 fixings (say soldiers at 600mm centres)

 

[dishman]

Cool - the three fixings were for the three coach bolts it that were an option as there are three pre-drilled holes in the girder.

I would just replicate how many soldiers were there already (7).

Whoever put the existing fascia used lost head nails. Decking screws sound like an idea.

Taa