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Decorating Grade II listed structure


(markyb) #1

Hi all,

My name is Mark and I run a small building and property maintenance company in SE England and in and around London.

I have for some time been providing maintenance for a group of wooden structures that are constructed of an oak frame in between which are panels of 10mm thick x 75mm wide tounge and groove (matchboarding) panels that are painted in green gloss.

I am encountering an ongoing problem with these panels which i believe is primarily due to changes in the weather.

In hot weather the timber expands and the joints in the matchboarding are pulled apart. Whoever undertook this contract before me filled these joints with caulk and decorated over them. If the joints are not filled, water ingresses into the joints and gets into the fabric of the building.

In the cold weather, the timber shrinks and the caulk is compressed, causing the decoration to fail again and round and round we go.

I was wondering if anyone had experience of a similar situation ? I was wondering if there was a decorators caulk on the market that offerred higher than standard flexibility that may get me out of trouble. My client is very understanding of the situation but my usual standard of decoration is very high and I am not used to having to re-decorate the same piece of work within two years !

I primarily use the Dulux Weathershield system and on all substrates other than these darn panels have had excellent and long lasting results. Whilst decoration is not my primary business I pride myself on my work and try very very hard to do the best job we can. Seven years in and I have still not had to advertise… must be doing something right !!

It is not possible to remove the panels and refit them without expensive and extensive and intrusive works, which on Grade II listed buildings becomes “complicated” I was thinking that the long term solution would be to add strengthening to the backs of the individual panels, maybe by gluing or fixing ply to the backs when they become accessible during a full refurbishment… but that doesnt solve my immediate problem.

Any suggestions chaps ?

As an aside, some of the timbers on these structures have been neglected and are badly weathered, open grain and severely silvered. Other than extensive preparation are there any products that promote paint adhesion and prevent premature failure ?

Thanks in advance.

Love some of the painted kitchens on here… have offered this as a cost alternative solution to a couple of clients :slight_smile:

Mark


(Russ Pike) #2

Hi Mark,

I do not know of a caulk suitable for exterior with such flexibility and if you find one let me know.
To be honest I would be more inclined to use:

http://www.sadolin.co.uk/homeowner/products/garden/superdecopaquewoodprotection/description

If you are thinking of removing the panels at some point I would refit them by secret nailing down the tonge say every 6" with a galvanised or brass pin and then applying cascamite glue: http://www.axminster.co.uk/cascamite-powdered-resin-wood-glue-prod21688/ to the groove before refitting. I’m surprised there is so much movement on what sounds like, not a very wide panel at 75mm.


(Andy Crichton) #3

This just in from our man at the ministry of sealants @UKsealants Alastair


(Aggie) #4

Dow corning 480 caulk could be tentative.

However, I feel that you are just treating the symptom as you suggest, usea ply sub-backing, especially if there is water ingress getting into the fabric of the building like you said. I am wondering if the match boarding has been installed upside down? Does seem extraordinary to be having so much expansion & contraction with such a small area of panel as well. Hmmm, another thought…remove the match boarding, attach breathable membrane behind. I would then have identical section machined up in hardwood such as oak or Iroko, which would be much more dimensionally stable. Then forget your gloss system, & apply water based opaque such as sadolin Superdec as a finish.
Be very careful with listed buildings, especially in conservation areas, the silvering of the oak beams you mentioned is a feature in some cases, altering this appearance could get you in to trouble.