Floorboards......a few questions

[Vic Wintergreen]

150 year old Victorian Terraced property
First floor
I have lifted the floorboards to put in a foil backed platsterboard wall. Spaced 25mm from the wall. Plasterboard extends below the level of the floor and above the level of the ceiling so there is a continous airflow path from below the floor into the roof void.
I was going to seal the gap between the floorboards and the wallboard with decorators caulk (this will be hidden by the skirting) and seal the gaps between the (straight edge) boards with a propriety gap sealant (Ronseal)
I have screwed the floorboards down with 10 x 1.75 brass cs screws
I have lightly sanded leaving some patina and character on the floorboards
I want to fill some of the deeper holes and would like some advice on the best filler for this job
After everything is complete I want to lightly sand then wipe down with boiled linseed oil mixed 5-1 with white spirit and then finish off with a floor wax
There ya go.
Have I made any mistakes (screwing vs nailing, sealing vs not sealing etc)
Do you have any other advice
Thanks in advance
Vic

 

[Nemesis]

Just a very quick post - saw this advertised, have no idea what it's like but it sounds useful:

http://www.gapseal.co.uk/?gclid=CNag3KK04JACFSZPMAodhiYJPA

Any number of ways of filling dents and splits etc, mixing a filler with sawdust is one:

http://www.wood-finishes-direct.com/products/wood-finishes/wood-fillers/wood-filler-gel.htm

 

[Vic Wintergreen]

Thanks for the quick reply
I saw the gap seal thing but it looks like it may not fit down between boards that are practically touching. I didn't square the edges as I wanted to retain the slightly haphazard nature of the boards and I have some gaps around 3/16" and some without a gap at all, well barely.
As for the filler, I have looked through Screwfix and Axminster (I have local branches) as well as an old school ironmongers.
I would like some practical reviews
I've used glue/sawdust and 1k and 2k fillers with varying degress of success in the past

 

[Ian Bond]

If the gaps are no more than a couple of mm, I'd leave them as they are.

You could use slivers to fill the larger gaps - wedge shaped strips pushed into the gaps, glued one side only, and planed flush.

http://www.oldpinecompany.co.uk/slivers/index.asp

I seem to remember that in the demo they were gluing both sides of the sliver - not a good idea, as you need to allow for seasonal movement, and gluing everything solid could lead to boards splitting.

 

[Vic Wintergreen]

Thanks again. The seasonal movement was what I was worried about with regards to screwing the boards down. I'm trying to leave them slightly loose, as it were.
Any thoughts on the air movement issues? I have seen diagrams where the floorboards have a gap between the wall and then the skirting board to allow air flow through from underneath the floor. The original build had the floorboards touching the walls all round, and then the plaster had been applied right down to the floor, so it was in effect a perfect seal anyway. I am trying to avoid problems that early builders were not aware of (or didn't care about). I have trimmed the floorboards back. As well as allowing airflow, it also makes them a little easier to lift should I need to. Originally I had to either cut the board at a joist or risk destroying the plaster as the board was lifted.

 

[Ian Bond]

Don't worry about the screwed down boards - it will not hinder seasonal movement, and will make it easier to lift for access. Also, it saves hammering vibrations from damaging the ceiling below.

There should be a small gap around the perimeter to allow for movement - you don't want the boards wedged tight against the walls.

I can't see air flow being too restricted by the skirting, and the walls aren't damp are they?

 

[Nemesis]

It may be that originally the room had no boards which is why the plaster reaches the ground. Where there are skirting boards, it's usual ti have a gap and the plaster not reaching floor level.

Where we have used screws to screw down boards, we have filled the holes with wax of the sort used in furniture repairs, which can be melted and colours mixed. It dries quite hard yet can be dug out readily if the screw heads need to be exposed.

I haven't used modern squidge to fill gaps, but I have seen it recommended. My experience of this stuff is that it can eventually dry out and crack a bit, so ensure you get one which can be fairly readily dug out and renewed in future. I think it's worth a try, alongside filling any larger gaps up with fillets.

Nothing lasts forever in this situation. Some people use papier mache, tinted to match.

 

[Vic Wintergreen]

There is a samll gap around the perimeter, this I will fill with caulk - flexible. The outer wall was damp, and after reading many articles (including some on this site) I decided that the damp was caused by the cement pointing repair to the outer (solid, lime mortar) wall and the number of heavy paper and paint coats on the inside preventing breathing. The plaster had blown and crumbled and had many bad repairs, including gypsum around the double glazing. (installed before I moved in). Following much research and many phonecalls I decided to install a cavity type inner wall. I repaired the damage to the inner wythe with lime motar and have treated all timber I exposed with Cuprinol 5 Star Wood Treatment. There was evidence of worm and rot in some of the timbers.

I think the layout is original. The properties were built in 1847 and consist of 11 terraced dwellings. From what I can make out the whole terrace was built in layers. Many of the cross joists are common with the adjacent properties and the floorboards on each of the 3 levels (ground/first/attic) are under all the features, door jambs, stairs, plaster etc. implying that each floor was installed then the fittings, then the next floor and so on. It does make it difficult to lift all the floorboards as they pass under door posts that clearly support features on the next floor up, so some have had to be cut. This all adds character to the house though. When I moved in there was even a 'live' gas mantle in one of the bedrooms. The previous occupant had lived there since 1958 and had done the 60's DIY craze things, hardboard over pine panel doors, brown mottled tile fireplaces (Wallace and Gromit style) etc. I think there was also a lot of quick fixing prior to the sale (1990) as there is a lot of evidence to suggest that the place had become very run down. These are the problems I am trying to sort out now. Bodged plaster repairs, heavy lining paper, millions of floor tacks. There was even a 13amp socket wired into the lighting circuit. That caused some concern as it blew the (old school wire type) fuse as soon as we plugged a kettle into it.
Thanks for all the help so far, and keep the ideas coming.
Vic

 

[michael]

Am I correct in thinking that one of your jobs is to fill the gaps between the length of the floor boards (perhaps as a draught excluder)? I had reasonable success some years ago using paper mache i.e. torn up paper mixed with wallpaper paste (powder) and water in a bucket. The paper mache mix can be squeezed down quite tightly between the gaps. I used the flat handle end of a stainless steel cutlery knife to work it into the gap and tap it flat. It remains fairly flexible when it goes hard i.e. it doesn’t crack along its length and moves a little with the board and like the wood, it absorbs the colour of the finishes put on the floor in my case stain and varnish but I think it would probably also work with oil, wax etc although it may still require a little stain (probably best to experiment on a small area first). I wouldn’t sand it once it has been applied particularly with a heavy sanding machine as I think this could dislodge it.
In my situation this method lasted about six years on a living room floor before showing signs of wear and needing attention by which time the floor needed a recoat anyway. How long do the proprietary floorboard gap fillers last? No longer I suspect.

 

[Vic Wintergreen]

Thanks again. I am aware of the papier-mache mix. I have a couple of concerns with this method. Some of the cracks are very small and may be difficult to squish the mix down, and the other is the fact that it dries completely, and may not remain flexible. I have resisted the temptation to router a step into the boards to provide a more uniform gap. Thanks again though for the input. All options will be considered.
Vic

 

[Toby Newell]

Yes I'm back, those who don't know me ask someone old and they will tell you what an annoying know-it-all I am.

Anyway... seeing as I just bought 42 kg of wood filler to fill floorboard gaps I must obviously have a slighlty informed opinion on the subject.

My opinion is I HATE filling board floors, board floors were not meant to be filled, parquet, okay, but boards are meant to move, unless you can actually loose a leg down there please leave them (and please ask all my customers to do the same) I don't know what has come into people, get a rug and enjoy the draft. I mean for three years doing floors I earnestly but ever so slightly dishonestly told all my customers gaps cannot be filled without immediately falling out again. For some unfathomable reason I cannot quite recall I relented and filled a floor, after that I had to concede it could be done and ever since 90% of my customers request it. I'm sorry.

Anyhow, I have developed my own special method of gap filling which whilst not perfect gives the best result and I don't mind sharing this trade secret as if I never have to fill another floor again I will be in heaven! Right...

First things first, most important point is to fix boards down securely using quality countersink screws SPAX or REISSER (can be filled afterwards) or cut brad floor nails, using packing spaces as necessary the movement of your floorboards/joists will determine how long your filler stays in. I don't have a clue what 10 x 1.17 stands for is that 10mm x 1.75 inch??? v odd metric and imperial or old no 10's? well scew them down tightly.

NEXT. Small gaps up to 3 - 4 mm can be filled with a resin and sawdust mix ( a modern far more effiecient version of glue and sawdust, which frankly is a joke) LECOL 7500 parkett mastic cellulose jelly filler is very good, bona mix and fill not so good, but no solvents. Larger gaps have to be filled with a thicker wood filler as the sawdust mix will fall through 5mm gaps and 4mm gaps will sink and sink... and sink.

RIGHT. Larger gaps. Ronseal high performance wood filler, Timbafill, Bondaglass, etc... All basically styrene based filler and benzol peroxide hardner. Exactly same formulation as car body filler, very flexible, can fill gaps of any size, very hard, sands perfectly, dries quickly. Problem. Wood version costs £10 to £20 a kilo. And you will need up to 10kg for a very gappy 25 sqm room. Go and buy some UPOL SMOOTH 7 car body filler or similar, should be around £20 to £25 for 6 or 7 kilos. It comes in a light grey colour. To colour it look out for UNIVERSAL STAINERS pigments, these are the very fine pigments in glycerine that are used to tint paints (the little squirts of colour in the paint mixing machines) buy these in yellow ochre and burnt sienna colours and mix these with the smooth 7 in the tin with a mixing attachemt on a powerful drill (its v v hard work!) presto. You now have 7kg of perfectly colour matched, smooth wood filler.

Please wear a gas mask as this filler is REALLY smelly and probably not good for you. You will need to tape up your boards at the edges and use a filling knife, mix a little at a time. I sand the excess off but you wont want to do that so you will have to mask the edges, this can be used to fill holes as large as 2 or 3 inches in diameter esp if you fix screws to the sides to give support.

I live in N London, if anyone wants to take my v expensive pack of reclaimed wood slivers off me feel free. Glue on one side. Yep and they still will ping up and give you harpoon like splinters, no thanks.

So the 2 pack wood filler (car body filler) LOOKS great, smooth and not a little bit like a slimy wavy worm of plastic like mastic does (Bona do gapmaster which is a coloured acrylic mastic sealant but at £4 a tube you will need around £100 worth of tubes and the forearms of hercules to do a gappy 25 sqm room)

The draw backs are it is v messy, v smelly, v tedious ( would take an inexperienced person at least a day or even a weekend to fill a 25 sqm gappy room) The results do look fairly impressive (I have countless pictures)

Personally I would live with the gaps and use the two pack wood filler for the larger holes and other damage. But then I'm biased, I've done it before. I think I shall go back to lying...

Toby

 

[Vic Wintergreen]

Thanks for the tips
The screws are 10 guage x 1.75" or 1 3/4" however you prefer
The largest gaps are probably about 5mm across, most are no more than 2mm.
Whilst I do appreciate the authentic gappy look the main problem I have is dust. I don't mind drafts at all, but I have developed asthma and the dust is being blown up from below the floorboards into the house. We have removed all carpets and as I lift the boards I am vacuuming the ceiling below.
As for the filler, well I spent 17 years in the automotive paint trade, supplying and matching paint and all associated ancillaries and have often used car based products in place of over-priced diy goods. It is very possible that my asthma developed due to exposure to high solvent levels in the mixing rooms. Thanks again for your help.
Vic

 

[Toby Newell]

So you know about upol then.

Actually for 2 mil gaps I would buy the Lecol 7500 and mix with sawdust, they also do a large filling blade which should make short work of the floor. I would get a small tub of Ronseal high performance 2 pack for the larger gaps and damage/holes. Well you know all about cellulose and 2 pack systems. Yeah I don't wear a mask or anything, prob why I've got asthma too. Lasco's even sell the Lecol 7500 now.

 

[Vic Wintergreen]

Yeh I had an account with Davids
Did you know that Isopon was a deliberate anagram of poison - hey ho
I found their Upol E and also Top Stop the best fillers. Super light and easy to sand. Currently have some Upol filler that I used on a recent speaker build. Dried quick and sanded quick.
Thanks for the help and advice
Once I get all the boards laid I will make a desicion
Vic