Explaining the benefits of insulating a summer home for year-round use.

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If your summer house is unusable for the majority of the year, it is a good idea to insulate it. Summer houses are lovely structures that are typically less expensive than garden rooms. However, they are not usually insulated, thus the name. This advice is for you if you want to repurpose your summer house as a garden office, or even if you just want to host an occasional garden party in there without freezing.  

You can then begin creating the most beautiful summer house ideas and make the most of this extra outdoor space all year. Here are the main factors to consider when insulating a summerhouse.  

(Photo by nigel FRANCIS / Alamy Stock Photo)

How should a summer house be insulated?

The first step in insulating a summer house is not the insulation itself. The first step is always to carefully inspect the structure for any structural damage that could jeopardize your insulating efforts. UValue Marketing Manager Daniel Murphy (Opens in a new window) , suggests inspecting your summer house for any holes or gaps where heat can escape. 'Caulk and sealant are only a few pounds each and will make a significant difference in keeping your summerhouse insulated. '

Once you've identified the problem areas, use quality caulk and sealant on the trim, the bottom edge of the siding where the edge overlaps the doors, where the roof meets the siding, in corners, and around windows and vents. This will completely protect the interior from the elements. '

After sealing, add your insulation. When it comes to choosing an insulating material for your summer house, you have several options. Some people are drawn to bubblewrap because of its low cost, but Murphy warns against using it, especially "if you want to add power to your conversion," because it "can be dangerous." If you don't plan on installing any electrics in your summerhouse, you can still use bubblewrap for a very basic insulation project.

Fiberglass is also not a good choice for summer houses because it can be a 'nightmare' to work with on outdoor structures. Fiberglass sheets are typically pre-cut, which can result in patchy insulation. They are also less dense than other options, which makes fiberglass slightly less effective as an insulator.

Murphy's preferred insulating material is 'foil-backed compressed insulation - it's easy to handle, cost-effective, has a high R-value, and is safe to use with electrics, making it an excellent choice for a conversion project. '

(Photo by Stuart Yates / Alamy Stock Photo)

Volodymyr Barabakh, Co-Founder and Project Director of Structural Beam Construction, (Opens in a new window) Another popular option is polyisocyanurate boards, which can be purchased from Amazon. (Opens in a new window) These are made of an insulating material similar to styrofoam (but more durable) and come in thicknesses ranging from 25 to 50mm. These panels, according to Baranakh, 'need to be cut to fit flush against the interior walls of your summerhouse (a jigsaw is required for this) and then sandwiched to the wall with an inexpensive wooden composite panel such as MDF or OSB board.' '

Tongue-and-groove cladding can also be used for a rustic look. Remember to bring your drill and insulation spray adhesive. (Opens in a new window) , which is available from Amazon  

The installation of cladding is simple, and it begins with creating a cavity gap for the insulation to go in with a few of your wooden panels. The insulation is then inserted into the cavity, adhered, and hidden behind the remaining panels or planks.

What is the cost of insulating a summer house?  

Polyisocyanurate and OSB boards cost around $2 per square foot when purchased together. If you are doing your own insulation, this is a cost-effective option. 'If you are going to do the job yourself, you can expect to pay around $200 for the materials,' says Barabakh. '

Expect to pay $400-$500 to have this professionally done, depending on the size of the summer house.

Foil-backed foam core insulation costs $5-$10 per square foot on average. It is costly, but its main advantage is its ability to reflect radiant energy, which keeps your summerhouse warm and reduces the need for heating. It's also simple to use.

Fiberglass insulation is much less expensive, costing as little as $1 per square foot. You must still factor in the cost of your wooden cladding. The price will vary depending on the specific material used; add $1 per square foot.  

(Photo by Zoonar GmbH / Alamy Stock Photo)

'You have the option of insulate summerhouses either internally (insulating the walls on the inside) or externally (insulating the walls on the outside),' says Barabakh. ' 

Internal insulation is much easier and less expensive to install, and most people prefer it. External insulation, on the other hand, may be required for smaller summer houses where space within the building is not a concern. '

You should also consider adding electricity to your summerhouse. Murphy suggests seriously considering this step because "it has the potential to be a game changer." You'll be able to customize your space with lighting and heating options. 'Keep in mind that running electricity to an outbuilding is not a do-it-yourself project, and you should not attempt it yourself. When it comes to electricity or any type of light-level electrical work, it's best to leave it to the pros. Spend some time researching and consulting with a professional to ensure that work is done safely. The price will vary according to the size of the job. '

Finally, think about carpets or rugs for your summer home. Add outdoor rugs if you live in a wet climate. They are recommended by Murphy because they "trap the heat much better than traditional wooden floors." The cost of carpeting is entirely dependent on the size of your space and the quality of the materials you wish to use. The price will vary because they are both a fashion statement and an energy-saving option. '