japan black floor disaster

[durwood]

Sorry,

I should have been a bit more precise:

I meant 2 pack polyurethane. The hardener will cure the paint regardless. So it will be rock hard to walk on or to reappply another coat.

Get actual black polyurethane, adding pigment to clear will not give as good a coverage if mixed in the maximum proportion allowed, and if overdone will decrease the servicability of the finish.

2 part Polyurethane is also great to apply it brushes/ rolls/etc easily.

I can't see you will have much trouble finding a supplier, if you do I'm sure someone in your area from the forum will be able to point you in the right direction.

[MacS]

I think some consideration should be given to the coating that he is going to use on the floor.

This floor has probably expanded and contracted many times over the years, and most likely is still doing that, the 2 pack coatings are very hard and once cured they do not expand and contract, and they are known to crack and lift on certain woods and in different situations like in this case, where there are seperate boards making up the floor.

In many cases the most durable and chemical resistant coatings are not the answer, this just maybe one of those cases.

I would thnk twice, and finish once.

MacS

[durwood]

Luisa originally posted that the floors were brand new. our weather doesn't have the extremes that the USA has from freezing snow to heatwave though it does get hot and cold especially in Melbourne so movement is not so great. I have friends in the States who's house has to be kept heated in the winter even though they don't live in it because of the freezing problems, that is something no one in Australia ever has to consider.

You can not stop any wood product from expanding and contraction at joints or faults and you have to live with the results of that. A hard serviceable finish like two pack polyurethane is extremely scratch resistant which is why its the choise of finishes on floors which are subject to high traffic.

If a floor timber is going to shrink any great amount no finish will be able to prevent the crack from forming.

Even paints which have flexing agents added to them to make them more elastic ( such as those used on plastics) still fail when the substrate cracks or shrinks and adding these decreases the hardness of the paint surface.

No matter how hard the paint may be it still may be damaged if the timber itself is soft. It will help in providing stength to the timber but enough pressure and it will fail. Most timber floor get marks on them especially if you drop something hard or woman wear stilletto heals.

I'm sure Luisa has considered this when choosing black as it will show marks probably more that any other colour but - thems the breaks. All you can do is weigh all the pros and cons and make a decision. even if we all have a different opinion.

[Gaza]

Luisa originally posted that the floors were brand new. our weather doesn't have the extremes that the USA has from freezing snow to heatwave though it does get hot and cold especially in Melbourne so movement is not so great. I have friends in the States who's house has to be kept heated in the winter even though they don't live in it because of the freezing problems, that is something no one in Australia ever has to consider.

You can not stop any wood product from expanding and contraction at joints or faults and you have to live with the results of that. A hard serviceable finish like two pack polyurethane is extremely scratch resistant which is why its the choise of finishes on floors which are subject to high traffic.

If a floor timber is going to shrink any great amount no finish will be able to prevent the crack from forming.

Even paints which have flexing agents added to them to make them more elastic ( such as those used on plastics) still fail when the substrate cracks or shrinks and adding these decreases the hardness of the paint surface.

No matter how hard the paint may be it still may be damaged if the timber itself is soft. It will help in providing stength to the timber but enough pressure and it will fail. Most timber floor get marks on them especially if you drop something hard or woman wear stilletto heals.

I'm sure Luisa has considered this when choosing black as it will show marks probably more that any other colour but - thems the breaks. All you can do is weigh all the pros and cons and make a decision. even if we all have a different opinion.

no timber manufacter in australia will recommend using 2 pac poly on new timber floors.

the US has differnt fixing methods, differnt timbers and sub floors the flooring is laid on, plus vapour barrier behind there wall lining. That is why 2 pac poly is used over there more.

here is the timber indsurty fixing manaul which states http://www.timber.net.au/documents/d...ing_Manual.pdf

Page 14
PROPERTIES OF COATING SYSTEMS (table)
Under poly

May edge bond boards#.

# Edge bonding relates to the finish acting as an adhesive and bonding board edges together. When board shrinkage occurs, this can

result in wide irregularly spaced gaps at board edges or splitting of boards.

boral timber flooring

http://www.boral.com.au/timberfloori...ing&site=Boral
says

* Boral Timber does not recommend polyurethane sealants because in some situations bonding may occur between boards which can result in a "clumping" of boards with irregular, large more noticeable gaps between random groups of boards, e.g. every fifth or sixth board

Timber flooring is not a concrete truck and your comprasson of the use polyurthane finish is not approiate.

[Gaza]

Black stain on a floor looks great, we did an foyer of an office building last year.

the stain was feastwaston mopped on and wiped off by hand.

3 coats of toby aquamax water based was then appiled.

still looks good today and has constant traffic inclduing high heals.

[Gaza]

This floor is new blackbutt

stain is a custom mix which contains black, floor is coated with two coats of bona mega watebased.

[MacS]

It was just a thought that was worth mentioning.

Two pack coatings are great coatings, but like all coatings they have their place.