How to build your own solarium the right way
How to build your own solarium the right way

How To Build Your Own Solarium The Right Way

By Mike Holmes

Mike’s Advice / Outdoor Renovations

Friday, June 15th, 2018 @ 3:16pm

Solariums are essential additions made almost entirely of glass, which can lead to a greater risk of heat loss. Anyone considering a solarium should only hire a reputable professional who addresses and minimizes that risk by getting all of the proper permits and by following the right construction protocols, including the building code.

The direction of Solarium

The direction a solarium faces will have a direct impact on the amount of sunlight it gets on an annual basis. For maximum sunlight, a solarium facing south is best.

sunroom from Holmes Family Rescue

Sunroom photo from Holmes Family Rescue

The Foundation of Solarium

You should build a solarium over a foundation, and it’s usually between three (3) options:

1. Frost wall. Footings with a basic block foundation on top – imagine a basement with the middle filled in.

2. Foundation with a basement. The solarium sits on top with a basement below it. Homeowners should note that this option costs more and will automatically extend the scope and timeline of the project.

3. Concrete slab with posts. A concrete slab is built on grade and then posts are driven through it to lock it into place, which prevents it from shifting or moving over time. The type of posts a contractor uses will make all the difference.[/one_half]

What Did Mike Do?

In an episode of Holmes Makes It Right – “Starting Again” Season 1, Mike built a solarium with a concrete slab foundation.

When it came to the posts he used the best: 3 Techno Metal Post’s helical pile drilled into place at the back of the solarium (the part away from the house), which are like giant metal screws that prevent the frost from grabbing them and pulling them up.

Only a certified technician can install these posts because it requires specialized hydraulic machinery that measures soil conditions.

This machinery will drive the giant screw down into the ground until it hits the right type of soil to properly anchor the foundation.

Glass of Solarium

The glass used to build solariums is different from the glass used for windows. Most windows today have double or triple pane low E glass. If this type of glass was used in a solarium it would lead to heat loss and condensation, which means the glass will be constantly fogged up, too.

To prevent this from happening solarium professionals use an exclusive multi-coat glass product that keeps the heat in during the winter, and out in the summer and blocks UV rays, all while letting the sunlight in year-round.

The number of coats each glass panel will have depends on where it’s being installed. For example, the glass used for the solarium’s roof can have up to 12 different coatings on the inside of the glass – not the outside. But the glass on the solarium’s walls will have fewer coatings because they will not get as much direct sunlight as the roof, and therefore do not require as many coatings.

The more coatings there are the darker the glass, so pros will use as many coatings they need but the minimum possible.

Fire Safety of Solarium

There is a limit to how much glass a house can have on either side depending on how close it is to the property line – not the fence, which can be along that same line – because of the risk of fire.

Building code tries to protect homes from spreading fires, and glass is one way they can spread quickly. The further away a house is from the property line, the more glass it can have on that side. But if a house is less than 4ft from the property line it can’t have any glass on that side, and therefore, no solarium. Also, keep in mind electrical fire safety as well. 

Cost & Time

Often homeowners will have unrealistic expectations about the size of the solarium, how much work is involved, how long it takes, and its cost. It’s the contractor’s job to guide you on what can and can’t be done, as well as your options. A properly constructed solarium can cost anywhere between $30,000-$50,000, depending on its size, and it can take approximately 2-4 weeks to build.


Solarium professionals include lifetime guarantees on the glass they use to build their solariums. These guarantees are transferable to new homeowners, so if the owner ever decides to sell their home they can include the guarantee as part of the package they present to prospective buyers.

Who Do You Hire?

The key to getting a properly built solarium is finding a reputable contractor to design a room that suits your needs. Hiring the right contractor takes some time but you need to find your ideal match. Only consider solarium professionals who have years of experience building solariums – the more, the better.

Signs you found a pro:

  • They will not give you a quote over the phone
  • They will not accept the job until they have seen your home
  • They will spend at least 2-4 hours speaking with you figuring out exactly what you want, what you need, and what can be done
  • They will ask you questions like, ‘How many people live in your home?’ and ‘What is the solarium going to be used for?

psstThe pros Mike goes to have been building solariums for over 40 years!

Make It Right®