Just before we start, many people have requested advice on how to cope with the gaps between the boards and whether they should be filled or not. I would not fill them for two reasons (1) I believe the filler would make the floor look like it was wearing pinstripes! and (2) the borads will expand and contract in a way that the filler won't, it will eventually crack. I recommend leaving it.
This page turned out a lot longer than I thought, you might prefer to print it out or save it as I'd say it will take about 10 minutes to read.
This is a "war story" about how we sanded and stained the standard builder's floorboards in our new house in Limerick, Ireland. I am NOT saying that we did everything right. But if you follow everything here you should get the same result, which is pretty good. I've included a few tips along the way.
Standard floorboards in Ireland are either "white" or "red" deal (or is it "deel"). Since I started this page, I have discovered that this wood is actually scots pine and usually comes from scotland, it is a softwood and the "white" variety is often referred to as "yellow". If you have floorboards upstairs then this is probably it. It is pretty OK to sand which is just as well because builders treat them with utter disdain and seem to assume that they will always be covered up by carpet. Therefore you will need to cut through the tea-bag, cigarette butt, paint and plaster stains. If you mention to the builders that you intend to stain the floorboards, they will tell you that you should have got much more expensive timber and wash their hands of you. They will take a little more care though, so it's worth mentioning.
Important points to remember:
(1) Sorry to say this, If I had my time over again, I would not do the sanding at all. There are people available who will do it for approx. 100 quid (about $130) a floor. They normally advertise by flyer or on community notice boards.
(2) Do rent a floor sander. This is a thing like a big Hoover that you stand behind and push. Don't do what I did which is start the job with a belt sander only, this will break your back as you have to kneel or squat with it.
(3) Get hold of an old Hoover that is on its last legs. This will be invaluable for clearing up sawdust, lumps of plaster odd nails etc. If you use a good Hoover the sawdust will probably kill it, or at best you will get a faint burning odor from it forever. The sawdust gets in the motor.
(4) Remember that the boards will shrink like crazy as they dry out, try and have them as dry as possible before you start. If you can stand the wait, don't start until the heating has been on for about 3 months for a new floor. However we did it after only 2 weeks and it turned out OK but we have been woken twice by loud CRACKS at night as two shrinking boards finally overcome the varnish gluing them together. It's not a problem though it doesn't do any damage.
(5) This is a big job, it took us over two weeks at a rate of a couple of hours every night and most of the three weekends to do 2 medium sized bedrooms. We did lose a lot of time due to using the belt sander instead of the floor sander though. Your friend that told you he did his entire upstairs in a weekend is lying. He should have said that he, his wife and the four brothers did it.
Try and have your builder replace any really damaged areas. You can use wood filler on small areas of damage but not too much. We used "plastic wood" on two small areas. In one area the filler later cracked where it came under pressure from shrinkage. No matter what the container says, it will not stain the same colour as the wood. I certainly would not use it to fill knot holes or nail/screw holes. We left the nail and screw holes alone. I think that if we had filled knot holes they would have cracked and filled nail holes would have stuck out very clearly. The builder did a lovely job on some of the larger knot holes by whittling away at a piece of the wood to make a plug and gluing it into the knothole. I can no longer find these repairs.
Hammer down any nail heads that are sticking up. It's worth getting right down to the floor to look for these nails as they will shread your expensive sand paper if you miss them. The sparks they throw up are impressive as well. While you're at it check that all the boards are firmly fixed in place and don't bounce, nail or screw if needed.
Take all the rough rubbish off the floor with your oldest Hoover. Don't kill yourself cleaning up as you are about to cover the entire house in sawdust anyway. Any stains on the timber will probably be sanded out or masked by the stain so don't worry too much. Pry up any silicone adhesive that's stuck to the floor as the sander will not even dent it.
We found that we needed 3 sanding tools; a floor sander rented for about 25 quid a day, a belt sander for about 20 quid and a heavy duty orbital sander for about 10 quid.
I also needed a transformer as two of the machines were 110 Volt. There was no charge for this but it did seem to trip the circuit breakers a lot.
We used three grades of sandpaper for all the machines; a really rough one of about 40 grit because the floor was very badly stained and discoloured, an intermediate of about 80 grit and 120 or even finer grit to finish. There are specially shaped papers for the sanders and they can be bought from the rental people for 2 to 4 quid per sheet / belt. The ones for the floor sander are the dearest, but they will take back any you don't use. You can make your own for the orbital sander from standard sheets of sandpaper that typically cost 30p. Our two bedrooms took about 3 of each grade / type (27 in all)but you will need spares as they will occasionally shread on nails or just of their own accord.
Get a series of dust masks or you will be spitting sawdust for a week. I had a pair of disposable overalls that were invaluable as well. I would really recommend that you have plenty of water with you, it's very thirsty work and you should consider bringing a couple of big bottles with you. Especially if you are trying to seal yourself into the room to keep dust down.
I would recommend doing the whole floor with one grade of paper and then switching to the next one down and doing it again. Start with the roughest grade paper and the floor sander. Give yourself about two third of the width of the room and sand along the length of the board. Never under any circumstances sand accross the boards, this will leave a horrible mark that will show through the stain and varnish. I can point out everywhere that I did this. Roll the sander towards one wall then tip it back and roll it back to the starting point. Make about two passes then lift it to the side and make your next run slightly overlapping the first. I used to do it as if I was sanding just one board, sand it twice then move it over to the next board. This worked fine as the boards were about 4 inches wide and the roller the sandpaper was wrapped on was about 6 inches wide. Don't swivel or leave the sander running in one position as it will cut deeply into the floor or even burn it. The one I had had a temperature cut out which shut it down once or twice. If this happens you, check the circuit breaker / fuse at the fuse board (it tripped loads of times on me), if this is OK it's probably the cut-out so go make some tea and let it cool down.
When you are finished heading in one direction, turn around and do the other third of the room. This stage should have gone fairly quickly and you will now have been lulled into a completely false sense of security. There will be about a six inch gap all around the room that you cannot get the floor sander into. Now the real fun begins.
To cut an extremely long story very short, the belt sander will get you to within about an inch and your only hope for the remainder is the orbital and good old elbow grease. Each one of these however is a further step down in power and step up in time required. This is by far the hardest part of the job so if you have lots of angled walls, radiators or fitted furniture to get under I would seriously think about carpet. There is a sanding tool called an "edger" which I could not locate anywhere in Munster which might make it easier. I also considered buying one of those "clothes iron shaped" sanders but was warned off that they were meant for furniture and wouldn't stand the pressure. Getting under things like a radiator and into corners is the hardest as all the tools are quite tall. I would welcome any advice from someone who has found the right tool for this job. I have since aquired a small low-profile grinder and will let you know how I got on if I ever work up the courage again.
So repeat the above process for the three grades of sandpaper, clean up, crack open a can of beer and admire your sanded floor. Prepare your own "war story" to tell everyone at work.
Things to remember:
(1) I've come accross differing opinions on whether you can mix oil based stains with water based varnishes (or vice versa), for safety we didn't. By the way, I mean mix them in terms of applying one on top of the other, I KNOW you can't mix them in a tin. If you're having trouble figuring out whether something is oil or water based check the "clean-up" instructions, if you clean up with water, it's water based, if white spirit is required, it's oil based. Water based varnish looks like milk in the tin.
(2) We used water based varnish because we were close to moving in and didn't want the unbearable smell of oil based varnish.
(3) Stir the living daylights out of both stain and varnish. If possible get the shop to mechanically agitate it or use a drill. check that all residue at the bottom is gone.
(4) We found the estimated coverage figures on the tin pretty accurate. If you're going for the first time make sure you have your room sizes in both metric and imperial, either could be on the tin.
Before you do any staining, rub the floor down with white spirit to pick up any dust.
The staining is by far the key part of the job. If you spill sweat and blood on sanding the floor (I did, literally, makes a nice cherry stain but I wouldn't recommend it), you don't want to finish by applying a colour that you hate.
We were trying to get a nice light "antique pine" look and we used a ronseal water based floor dye of that name. We were very careful and applied some to a scrap piece of wood from the skirting boards and to two patches that would be under the bed. The only trouble was that we got three pretty different shades. The lightest (and best) was the skirting board sample, but as we could not reproduce that shade on the floor we concluded that the skirting must be a different timber (perhaps "red" rather than "white" deal, or vice-versa) and gave up.
The two shades on the floor were very dark (bad) and moderately dark (OK). The differences between them were that one was simply brushed on by myself and the other was brushed on and ragged off by my wife Anne. Looked like I was out of a staining job! All that applying the stain involved was brushing it in sections about two boards wide by three feet long and then rubbing it off with a cloth before it got too dry. Use a cloth that won't leave fluff and apply the last rubbing motion in the direction of the grain (along the board).
We left this overnight to dry and then applied the first coat of a ronseal water-based clear satin varnish. We were advised to dilute the first varnish coat half and half with water as the floor would really soak it up. We allowed this to dry for five hours and then rubbed the floor down with fine steel wool and made another pass with the white spirit.
The steel wool is to knock off any dust that settles into the varnish and to grind up the surface of the varnish so the next coat gets a better grip. We did three varnish coats with a steel wool and white spirt job between each.
This gave us a finish we were perfectly happy with. However it does not look like any antique pine I've ever seen. The final colour is a moderately dark orangey-brown but perfectly acceptable. Like this
For the second room we tried to lighten it by starting with a half and half mixture of varnish and stain followed by two more coats of straight varnish. This worked very well and gave us a slightly lighter finish. Like this.
I suspect you could dilute the stain further if you wanted. If you go too far you can always apply further stain. The colour you get when the stain is dry is the final colour. Clear varnish does not do much to the colour.
The best antique pine tone I've seen was made by a company called Rustins. However someone else did that job so I don't know how it would have come out if we did it.
Well that's it. Hope our experiences were some help. Add an entry to the guestbook if you have any comments.