"Damp" timber frame, what to do?

[ProDave]

Our house is all timber frame.  The frame between the house and the garage has been left open on the garage side for some time, and the garage has been used for storage of just about anything and everything.  I have just emptied the garage in preparation to plasterboarding it and finishing it and I found this:

 

My first thought was bugger, there is a problem with the DPC. But that is not the case.

 

I have removed the timber skirting, and peeled back the DPM and it reveals a bone dry sole plate with no staining so it is not coming up from below.

 

I now think the staining is the result of something being spilled while in storage. There were some pallets against that wall and all sorts of stuff was on them as makeshift shelves.

 

The stained area feels dry, perhaps slightly waxy? and has no smell and is still completely solid.  Best guess is a bottle of car wax polish may have leaked.

 

Question is, what if anything should I do? Treat it with something?

 

 

[Cpd]

The wood is already treated C16 I expect. It’s dry so Just ignore it and carry on would be my suggestion. 

[Redoctober]

@ProDave looks like the issue may not be as first feared. Fingers crossed that is the case. However, 

 

1 hour ago, Cpd said:

The wood is already treated C16 I expect. It’s dry so Just ignore it and carry on would be my suggestion. 

 

We have such timbers [may even be C24, I don't know for sure] on our fascias, soffits and gable ends etc. It has been suggested that I should start to stain  / paint them, so I started with a preservative primer today. Is that really necessary given the above or is it a case of " can't do any harm etc. 

We do intend to paint them once we have agreed on a colour and the next step with be an undercoat. 

As ever, I welcome your thoughts.

[ProDave]

I am pretty sure these are all C24 timbers.

 

My worry is not that they are "wet" still and will rot, but whatever unknown chemical has soaked into them might not be good for them in the long term.

 

If it is as I suspect car wax polish will that do any harm?  The only other thing it might be is oil, but I am sure that would smell of oil.

 

I am absolutely confident the timber is dry now and there is no issue with damp getting in (sole plate bone dry and no staining) so this is the result of a spill of something and no more.

[Cpd]

Treated timber such as dimensional 6x2 etc are treated but I WOULD not recomend using these outside without further treatment. The reason I say this is because I get given all the old wood from the builders yard that’s fallen of the back of the stacks or is dirty / damaged. The stuff that’s been lying for a few years definatly does start to rot ! I have primed and painted this timber and it’s been fine but an extra treatment of quality preservative would go  along way to extending its life I think. If the wood is not going to get wet then I think it will be fine.