Monday, September 11, 2006

Deckhead insulation

Deckhead insulationI've made a start insulating the deckhead (ceiling) of the stern accommodation.

I'm using Celotex boards in the overhead space, rather than the spray foam I've used elsewhere, because it's very likely that I'll need to access this steel again - as part of the galley refurbishment project which is on the horizon.

The spray foam is a pretty permanent solution, as it will not come off too easily, so Celotex seems the best option here.

Cutting and fitting the Celotex has proved to be a tedious task, as each section has to be measured, the board cut on deck then brought down below, because the uncut Celotex boards are too big to fit through the hatchway.

What I'll do is spray any gaps between the steel and the Celotex with spray foam insulation, so as to fill the voids which would otherwise be impractical to fill. This will ensure that all the steelwork is adequately insulated.

Spraying that foam insulation is, unquestionably, so much faster and easier.


  1. Hi Tim I guess that there is no chance of any condensation collecting between the steel deck head and the celotex board thus degrading any !Paper sort! of insulation board? My recollection of celotex is that it was of a paper /wood core? I may be wrong and it may be of something more long lasting so please forgive me if that is now the case and I am off on the wrong track. Take care!

  2. Hi Rob

    My understanding is that the Celotex board is made of expanded polyurethane, so condensation should not be an issue.

    I think that gluing a sheet of plasic over the whole shooting match, just before starting to put the ply on would be a good move, to stop the condensation.

    What do you think?



  3. I would speak to a timber frame house builder as I think that a permeable (one way) membrane is needed, to allow the fill (insulation etc) to breath and thus not get condensed upon and rot but as to the technicalities I am not sure. Timber frame houses have a non permeable outside ie felt and a breathable membrane inside and then foil backed Plasterboard, to assist with the deflection of heat etc (obviously they have insulation in between)if I remember correctly? so if you imafine that you have a steel hull as your non permiable membrane I would guess that it would be wise not to encourage any damp air or moisture to sit in the void, so a oneway permiable barrier might be the answer. Im getting a bit lost here, but a search on google on timber frame insulation etc might help. I do like the idea of the sheet of polythene all over the inside but I am not sure that it would be the right thing as it will, most definitely keep moisture in the void and probably encourage it to occur in cold areas!
    sorry I cant be more informative but its meen along while since I have been involved actively in such things. Perhaps it would be better if I kept my mouth shut in future? :o)) You are doing a great job by the way.

  4. Hi Rob

    Your comments are greatly appreciated, so no worries there.

    As you say, the one way membrane sounds worthy of pursuing.