What is this green papery layer on timber floor?

[Juliette]

14 Oct 2016 Update : NOT Asbestos (per NATA accredited laboratory)

I hope someone can assist me — I am renovating a late 50s/early 60s kitchen.
I removed vinyl sheeting from the kitchen floor, then the stapled masonite over the original cypress boards. Beneath the masonite is a green papery/powdery layer.
Does anyone know what this is?

[Lappa]

Looks very much like mould. Is there signs of the area being damp at some time? Be careful just in case it is mould as you shouldn't breath the spores in.

[shedbound]

If not mould, could be the remnants of old vinyl tile glue, if it feels somewhat like foam.

[Juliette]

Thanks Lappa. Initially thought the same but no it's not mould. I can sniff out mould a mile away.

[Juliette]

Thanks shedbound, you may be right!
It is flattened out in most places except for around the edges of the stove, where it hasn't been stepped on.
And yes it is foamy. I would imagine the original 50s/60s Lino was stuck on that, then they tried to take it up (parts of it have been manually scraped), then they gave up, and layed the masonite for the flat surface for the vinyl Lino.
I'll be wearing a mask anyway but is there a possibility the "old vinyl tile glue" had asbestos in it?

[Xanthorrhoeas]

The tracery of fine dark, branching lines on the timber in the lower left of the photo looks like fungal hyphae - which can be thought of as similar to the branches and stems of a plant. That means that whether or not the green stuff is mould the timber has been subject to fungal growth and should be treated for it before you cover it up. It also makes it very likely that the green stuff does have some fungal content, not necessarily spores though.

I know that early vinyl tiles often, perhaps always, contained asbestos fibres for strength but I do not know if the adhesives used contained asbestos. It would be best to act very cautiously in case any tile fragments with asbestos remain.

[Xanthorrhoeas]

Are you looking at old adhesive that was under lino or under vinyl? I am not expert but I have not heard that lino contained asbestos, although vinyl (sometimes?) did.

[goldie1]

It could be the remains of a paper underlay which used to be layed under linoleum so the

floor boards didn't show through or it could be the remnants of the rubber backing

of "kitchen carpet" which was popular in the 70s

Black Jack tile glue which contained asbestos was a tar like substance

[goldie1]

Are you looking at old adhesive that was under lino or under vinyl? I am not expert but I have not heard that lino contained asbestos, although vinyl (sometimes?) did.

Vinyl sheet flooring from the 70s commonly had asbestos backing.

Have a look here http://www.deir.qld.gov.au/asbestos/...factsheet4.pdf

[Juliette]

Are you looking at old adhesive that was under lino or under vinyl? I am not expert but I have not heard that lino contained asbestos, although vinyl (sometimes?) did.

This green foamy/papery layer was under stapled masonite boards. I think the masonite was put down after the layer over the "green" was removed. I don't know what was originally over the "green" layer.

After reading other replies, the original layer over the "green" may have been vinyl tiles, Linoleum or kitchen carpet.

[Juliette]

It could be the remains of a paper underlay which used to be layed under linoleum so the

floor boards didn't show through or it could be the remnants of the rubber backing

of "kitchen carpet" which was popular in the 70s

Yes, could be carpet underlay.

Black Jack tile glue which contained asbestos was a tar like substance

Thanks. Definitely not tarry or black, so rules that out.

[Xanthorrhoeas]

OK, you are probably in the clear for asbestos, but should still take precautions, just in case. Are you planning on polishing the cypress floor?

Are you sure it is cypress? I have never seen fungal attack on cypress.

If you are going to sand and polish you may remove the fungal hyphae tracery but the outward signs of fungus (hyphae, mushrooms etc.) only mean that the adjacent substrate is riddled with the almost invisible fine feeding hyphae so, after sanding a good fungicide before polishing would be a good idea (if there are any that are compatible with clear finishes?).

[China]

It is the green paper backer used on vinyl decomposing, I have seen it many times and yes it may well be contaminated with Asbestos, make certain you are appropriately
protected.

[Juliette]

Thank you everyone for your advice and time.
I decided to have it tested and it came back as NOT containing ASBESTOS.
I sent it to Clearsafe ( NATA accredited).
I will still wear a mask when scraping it off but can relax when washing my work clothing and, when people visit, esp children.

[Juliette]

OK, you are probably in the clear for asbestos, but should still take precautions, just in case. Are you planning on polishing the cypress floor?

Are you sure it is cypress? I have never seen fungal attack on cypress.

If you are going to sand and polish you may remove the fungal hyphae tracery but the outward signs of fungus (hyphae, mushrooms etc.) only mean that the adjacent substrate is riddled with the almost invisible fine feeding hyphae so, after sanding a good fungicide before polishing would be a good idea (if there are any that are compatible with clear finishes?).

Pretty sure it's cypress as the rest of the house is. The photograph is from the pantry floor which is a few feet away from a leaking shower. The board and skirting in the corner closest to the leak have rotted (I think it's called dry rot?).
The initial pre-purchase pest inspection unfortunately didn't pick up the corner rot (would have purchased the place anyway!) and, also, he had no accees to the floor (covered in vinyl and masonite).

Another pest bloke is coming out to deal with the severe cockroach infestation (the moisture and decaying timber must be an attractant) and I will ask him about the signs of fungal attack you noticed.

Normally, I would polish the floor but with the damage already done and my aversion to cockroaches, the knotty cypress will be painted. Looking at Feast & Watson Floor Paint.