Roofing is a critical part of your tiny house build to get right; it’s the main barrier to keep you protected from rain, snow, and falling debris, and it plays possibly the biggest part in insulating your home. Installing your roof is a simple process, but a few key things need to be done to make it weatherproof, and getting it right the first time will save you time, energy, and headaches down the road.
We’ll go through the process of installing a roof step by step below, but before we get into the actual roof install, let’s go over some important aspects of different types of roofs.
Styles of Roof
There are quite a few different roof styles and shapes you can install. Some have actual benefits like a high run-off rate, while others are just for aesthetics. There are six main roof styles: gable, gambrel, mansard, flat, hipped, and shed (also known as lean-to). There are other roof styles out there, but these are the most common.
Each of these styles has different variants as well. You’ll often see doggie dormers as pop-outs on gable roofs, multiple hipped roofs butting up against each other at different angles, and some people have flat roofs used as an additional layer of square footage like in this tiny house with a rooftop deck.
Regardless of the roof you choose to install, pitch is something you’ll need to consider carefully. Pitch is the angle at which your roof sits relative to the ground. For example, a flat roof has no pitch, while a gable roof has a large pitch. The pitch will determine the rate at which rainwater runs off of your home. This is critical because the less time the water sits on your roof, the less of a chance it has of getting inside your home.
Common Roofing Materials
The most common materials used for roofing include asphalt shingles, metal roofing panels, and ceramic or clay roofing tiles. Each of these also has their pros and cons.
Asphalt shingles are very durable, but they’re also very heavy, fairly expensive, and are rather difficult to install. Metal roofs are less durable, but they weigh far less than asphalt shingles and are also cheaper and much easier to install. Clay roofs are heavy and extremely expensive, but they have the longest life span by far.
For ease of installation, low cost of material, and average durability, we recommend a metal roof for your tiny house build, and we’ll be going over how to install one step by step below.
How To Install Metal Roofing On Your Tiny House
We’re going to assume that by this point you’ve constructed the sub-floor of your home and have framed out and installed the exterior walls. Before you install your roofing you should also have chosen a roof style and installed your rafters.
Install Roof Decking
First you’ll be installing roof decking which will be made of pressure-treated plywood or OSB. This will span the gaps in your rafters and serve as the platform on which we’ll install everything else. This step is as simple as using a framing nailer to nail sheets of plywood/OSB to your rafters and being careful to stagger the seams of the sheets to prevent weak spots. We’d be remiss if we didn’t tell you to be careful! Working on a rooftop that isn’t decked yet can be very dangerous, so always stay alert and cautious.
Install Roofing Paper
Next you’ll be installing roofing paper, one of the most important layers to waterproof your roof. This paper comes in large rolls and can simply be rolled out over your decking and stapled down with a staple gun or tack hammer.
When installing roofing paper it’s imperative that you begin at the lowest point of your roof and work up toward the top of the pitch, and always overlap the previous strip of roofing paper by a few inches. This will help prevent water from running off of one strip and under the next, ultimately winding up in your tiny house.
Lastly, apply roofing paper tape to all seams in the paper strips to seal your roof properly.
Install Drip Edge Flashing
Now that you’ve prevented water from getting in through your roof, you’ll install drip edge flashing to prevent it from getting in around the sides. Drip edge flashing comes in long metal strips bent at 90 degrees along the length, and it’s installed on the corners of your roof deck with roofing nails. You also have the option of applying a bead of roofing cement to the flashing before installing for additional protection.
Install Your Metal Roofing Shingles
At this point you’re ready to install the last layer of defense against the elements: your roofing panels. Metal panels are very easy to install and just involve nailing the sheets of metal to your roof deck with roofing nails.
You’ll want to make sure that the corrugation in the panels runs from high to low to allow water to run off down the roof in these channels. Additionally, just like with the roofing paper, you need to install your panels beginning at the lowest point of your roof, work toward the highest point, and overlap all panels in each direction (top to bottom and side to side) for the best protection possible. Lastly, you should stagger the seams of your roofing panels. This may involve cutting panels to size, but keeping water out of your home is worth any effort.
Roofing is one of the fundamental and most important parts of any tiny house build, and while installation is simple, getting the nuances we’ve outlined above correct can be the difference between a strong, weatherproof tiny house and constant leaking issues. Make life easy on yourself in the future and install the multiple layers of defense on your roof properly the first time.