Hull Insulation

Since we first moved aboard Circe full time we had always intended installing some hull insulation to generally improve temperature control and help combat condensation but, as is often the case, we had never quite got around to it. So, during a recent spell of cool weather while we  were at a bit of a loose end we decided to make a start. But, what to use?

We had previously researched numerous insulating materials, looking for something that would satisfy two conflicting requirements: flexibility, without being too thick (for ease of installation into difficult areas) while still having a useful R value. We soon discovered there are lots of products that offer good R values in varying gauges but they are mostly rigid or semi-rigid structures that would require a lot of work to get into the boats various nooks and crannies and would reduce the size of lockers and storage areas. Conversely, the thinner gauges of more flexible materials, that are easier to work with, don't typically have very good R values. Making things worse, the more we read about radiated, convected and conducted heat transfer the more confused we became!  

So, finally, we decided to just jump in and try something. We chose to use Reflectix, which is primarily a radiant barrier product, with a rather low (R4) value, but it is very flexible and easy to work with, in either single or multiple thicknesses. We decided to make the main cabin our beta site and based on real world results over the next year we will decide whether or not to use it for the rest of the boat or look for another material.

Reflectix is very inexpensive and is readily available from any home improvement store and is easily installed using contact cement.








We used double and triple thickness wherever there was enough room and a single thickness where there wasn't. Despite its easy of handling it was still a fiddly business cutting the Reflectix into the weird shapes needed to cover the compound curves of the hull and underdeck areas, and to get round the various hose and wire runs. 

Here is the forward locker behind the settee.

This is the aft settee locker in process.

This is looking up into the forward cupboard above the settee on the starboard side showing the under deck area inside. Because of the deck step in this area it took several attempts before we got the right shaped pieces of insulation!

 

Here is the under deck area above the settee with the trim strip and panel removed to show the insulation.






We eventually covered all the accessible deck and hull areas in the main cabin, down to just below the waterline, with the Reflectix. To determine the benefits of the insulation, if any, we will have to wait and see how it performs in the various temperature and humidity conditions we experience over time. We plan to publish a review and update of this post in early 2015, by then we will have info on both summer and winter conditions. If the Reflectix proves beneficial we will complete the rest of the boat, if not we will again look for alternatives. Stay tuned!