Monday, August 14, 2006

Two part polyurethane expanding foam insulation

I've been looking forward to making this entry for some time now, and it's all turned out so much better than I'd dared hope.

Back in January, I began researching the best options for insulating Lady Jane, and found Spray Foam Insulation Ltd. After a trial, where I experimented with a small spray foam kit of two part polyurethane expanding foam insulation, I found that the spray foam worked really well over bitumen paint.

Of course all this went into my blog. As a result I got an excited call from Chantel, of Spray Foam Insulation Ltd, as folk were going to her website via my links.

After trading e-mails, and some phone discussion, I bought one of the large spray foam insulation kits, back in February. There was me thinking I'd be spraying sometime then!

Shortly after actually buying the spray insulation kit, and after a blog entry where I mentioned Bruce Roberts, a site worth visiting by the way, Chantel offered to come down to help me with the spraying. It turns out that Chantel and her husband, John, had bought cutting plans from Bruce Roberts and will soon be building a steel boat of their own.

I suspect a new boat building blog will be hitting the internets sometime soon.

Two part polyurethane spray foamOnce I was finally ready to spray, I emailed Chantel and they arranged to come down the very next weekend. In the event, Chantel and John proved to be a wonderful couple. After a quick lunch in Fareham, we got to doing the actual spraying.

The picture shows the insulation sprayed on the port side of the stern accommodation space, with a picture of Chantel getting ready to start spraying in the inset.

So far as I'm concerned that's the best endorsement of a product, where the owner of the business is happy to come down to help me get going with it. Ok, I know that some of it is marketing for the company and some is the interest in my boat project, but still...

The two things that really stood out in my mind were firstly how fast the spraying went and secondly, just how much area we managed to cover from those two, relatively small looking, bottles. I still have some spray foam insulation left in those bottles, despite doing most of both the port and starboard sides.

I've so far spent about three working days putting battens in, easily over 100 metres of the stuff, but these were all sprayed around in literally the space of just over an hour or so (not including a long tea break). What a pleasure in comparison to cutting boards.

I've yet to put the remainder of the battens in, and finish spraying the rest of the hull in the stern accommodation, but the back of the spraying project has been well and truly been broken, and I believe I'll finish the rest of it fairly quickly.

After the spraying was done, we settled down to a relaxed barbecue (braai) with some other friends, Colin and Arianne.

Good food, friends, a few beers (ok so it was quite a few beers for some of us by the end of the night) and some wine on deck in the afterglow of a successful day, what more could one want?

Special thanks to both Chantel and John, who are welcome back anytime.

By the way, if you have a boat, or anywhere for that matter, needing insulation, you should at least check out Spray Foam Insulation's website at, or call Chantel for help and advice on 0870 766 8556, Mon - Fri 9am-5pm UK time.


  1. We used on the Bowie. It also happens to be the business our landlord is into though on a much larger scale. They have a pumper truck and we had strung the hoses down the docks and over a couple of boats.

    However, since the Bowie is a wooden boat and it is highly unlikely that it will ever be a charter vessel again, we opted for the spray foam. Transport Canada (who governs all things marine) frowns on it apparently. It is probabably fine in everything else but wooden vessels mind you.

    It has made a heck of a difference. However if you have to scrape any of it back it is a static-y mess and god forbid any of the stray bits get in your eye or anything as it is quite painful even when dry. Misting over it with a spray bottle of water cut whislt you scrape helps keep the static down a bit.

  2. wahey the squirty foam moment!! you're going to be so snug come winter.

  3. Hi Bowichick

    I'm really motivated to get this insulation completed.

    It's already so much brighter down there.


  4. Hi there Seb & Becky

    I'm so looking forward to the snug bit, especially after staying on board last winter.


  5. That looks really good and very professional!

  6. Can anyone advise HOW one smooths off the solidified foam afterwards so that the hills and valleys which result from its natural expansion can be turned into a SMOOTH surface on top of which one can then paint, or glue wallpaper or attach luan strips or otherwise have a reasonably smooth surface to work with? It would seem that the foam can be sanded but how does one sand it both flat and reasonably smooth? I am sure there is some custom in the trade that is used but I don't know if it is a planer, sander, machete or saw. All suggestions welcomed.
    Elliot Miller
    Miami, Fla.
    305 534 1313 or
    Thanks a million and good luck

  7. Chantel6:45 AM

    If you want a flat smooth finish, spray between battens (the battens must be the same depth as you want the foam) and then use the battens as a cutting guide. Lay your saw or knife across the 2 battens and cut the foam back (you would have to do this section by section - filling in the battens with foam once you have removed them). Afterward, use an orbital or belt sander to smooth off the foam.

  8. Wow. I have been looking for information on Lynchburg foam insulation. But that's when I came across your post. This is awesome. I have not seen anyone do this on a boat before. Thanks so much for sharing.