Building The Perfect Cabin Roof Part 5 of 5

Well, it’s day #14 of the off grid cabin build and we’re about to complete the roof fraiming for our cabin.

Over the next two days we’ll build and attaching the roof rake ladder, close the roof up with OSB, and build a set of stairs for the front deck.

As you know your roof is a integral part of the build and requires extra attention. Be sure to review our Ultimate Roof and Rafter Guide prior to starting your roof build if you haven’t yet been through it. It will answer a lot of questions you may have about framing a roof and explain exactly why we did ours the way we did. You can also quickly go back and review the entire roof build for our cabin using the following links…

If you’re brand new to our site and just landed here, then you’re welcome to head back to the beginning of the cabin build here or better yet subscribe and we’ll send you a personal update every time we hit a building milestone. Plus, we’ll take you back to day #1 of our cabin project and walk you step-by-step through the entire building process.

Ok, get ready for an extra detailed and juicy post!

The Roof Rake Ladder

The roof rake ladder, named so for its resemblance, can be one of the more complex components when framing the cabin roof but stick with us and we’ll crack its quirky code to arm you with some excellent tips and tricks that’ll make you a ladder building expert in no time!

After we’ve attached roof ladders to the off grid cabin we’ll top off the roof with some OSB and call it a day. Actually, we’ll call it two days ;)

Here’s What You’ll Learn…

  • The purpose of the roof rake ladder and its components.
  • Why it is a critical roof structure and plays a role in the longevity of your home.
  • Important tips and tricks during the design phase that can create a more livable environment inside of your home all year round.
  • How to properly design roof ladders to last any environment and weather.
  • Our own technique for installing them properly on site.

West-Side-Roof-Ladder-Transision

Before we dive into our cabin ladder design and installation, I want to offer you up a basic Roof Rake Ladder: 101

This way we’re all on the same page using similar jargon.

If you’re already comfortable with constructing roof ladders feel free to scroll down and see how we installed ours.

The Roof Rake Ladder Details

You’ll recall from our section on Building the Front Deck Rafters that the cabin’s front and rear overhang are created by extending the bottom portion of the rafters out past the wall top plate or deck header beam. This is the section of the roof where you typically find the eaves-trough used for catching and diverting rain.

The ladders create the required roof overhang on the remaining sides of the roof structure.

Roof Rake Ladder Framing Design

Purpose of the Overhang

The overhang of a roof might simply seem like a nice added touch, but its serves a very real and important function. Their size (how far they protrude) and construction are important and can make or break (literally) your roof.

Large Roof Overhang

The roof overhang serves six basic purposes that warrant their placement on all sides of the home.

  1. Reduce the amount of rain that hits the exterior of the home
  2. Protect the foundation from excess water runoff
  3. Help to regulate the temperature of the home
  4. Provide protection for doors and entryway
  5. Help to shade windows in hot weather
  6. Keep basements/crawlspaces dry

REMINDER: During the cabin planning phase you’ll recall that when we purchased our land we considered the following which also plays into our roof design.

  • orientation of the roof to the sun’s path
  • optimum solar panel pitch
  • typical live loads our roof would experience based on seasonal weather (snow and wind)
  • typical annual rainfall for the area

There are additional factors as well that can best be taken into account now that you’re actually there at the build site. When you’re up on the roof you can get a much better idea of how big you want to build your ladders to account for the local tree shading. Ask yourself… How’s the shading up there? Is there any? Is there any nearby threes that are likely to create the shading required?

NOTE: We have many fast growing red and black spruce trees around our cabin and while they may only provide partial shade now, in a few years that will change. Just something to think about when considering the balance between solar heat gain and the cooling shade you desire.

The view from our roof top.

View-From-Above-The-Deck-of-The-Off-Grid-Cabin

Problems

The overhang plays a large role then it comes to your home’s internal temperatures and the exteriors preservation.

Overhangs that are too big: The interior of your home will be dark and gloomy. As well, your roof can become more susceptible to wind gusts causing roof lift. The amount of snow carried by your roof also increases.

Overhangs that are too small: Does not provide enough protection for the exterior of the home. A house without adequate overhangs leave the siding unprotected and vulnerable. Unprotected walls suffer high rates of water entry, premature failure of paint or stain, and premature wood/vinyl siding failure.

No Roof Overhang

Below: Rain can drip straight down contacting your foundation which will result in deterioration under the footings and adjacent to a foundation. As well, increased splash-back is responsible for a lot of siding rot.

Roof Overhang Splashback

You may recall during our How to Build the Perfect Foundation phase our cabin is resting on six pads. Each consist of 16” x 12” x 8” cinder blocks on top of 24” x 24” concrete pad (patio stone) which rests on a bed of leveled crusher dust and finally the undisturbed soil.

Setting the foundation pads

With an undersized overhang, water dripping near one of those pads (even for just one season) could easily cause the cabin to no longer be level. This stresses the wall framing, the interior wall finish (drywall), the trim’s fit & finish, and can even crack windows. That’s an expensive fix that can easily be prevented with proper roof ladder planning and installation.

An ounce of prevention is worth a pound of cure at this point.

It’s easy to think that the overhang is just… an overhang. But they serve a real purpose. A proper design, size and build will ensure you never run into these problems.

Notice in the photo below that the overhang is correctly being used to shade the windows and provide shelter over the patio doors.

Large Roof Overhang 2

There are “mathematical rules” and “architectural guidelines” that can aid you in determining the optimal roof dimensions. These guidelines are useful for any gable, cantilevered or flat roof design. Sustainable By Design has a page of free design tools which include an overhang recommendations tool.

As mentioned previously, you need to consider the balance between solar heat gain and the cooling shade you desire.

Roof Overhang Calculation For Optimum Sun

Roof Rake Ladder Construction

Components of the Roof Rake Ladder

  • Lookouts
  • Fly Rafter or Barge Rafter
  • Ridge board/beam

Gable End Roof Rake Ladder with Double Rafter (1)

You can see the ladders are composed of several pieces. These are the lookouts which run perpendicular to the rafters and form the “rungs” of the ladder. The lookouts rest on top of the gable end plate.

Next is the fly rafter or barge rafter. At the front of our cabin we used a 2″ x 6″ to connect all the ends of the rafters together forming the fascia. Here the fly rafter is used to connect the ends of all the lookouts together.

NOTE: The double rafter shown above is optional. This style is often used when building your ladders on the ground and then bringing them up to attach. Our ladders are being built one lookout at a time. We simply attached each lookout directly to the last common rafter and therefore did not require a double rafter. You’ll recall in our How To Build The Perfect Rafter section we have a rather unique rafter design and one that is incredibly strong and resistant to twisting.

A roof ladder can also be built without resting the lookouts on-top of the top plate as seen below. However, this is usually reserved for smaller builds such as a shed or a small addition.

Gable End Roof Rake Ladder Framing Short and Long Overhang

We’ve included a video from Henry of Country Life Projects & Living. He’s building a simple backyard shed but it demonstrates the small overhang build principles using the extended ridge beam method. 

 

Our Ladder Design

The first step of our roof ladder design is to ensure that the 2” x 6” front fascia board, which as mentioned connects all the rafter ends together to form the eaves, is at the proper height. We do this by using a scrap piece of wood to act as a gauge and attach the fascia. The end of the fascia will serve as the starting point to build the ladder(s) off of.

Aligning-Fascia-on-The-Off-Grid-Cabin-roof

Next, we completed the gable end studs over the deck.

The-Off-Grid-Cabin-Roof-Rake-Ladder-Framing-Over-The-East-Deck-Complete

This area above the deck will serve as a storage/crawl space when the cabin is complete and accessed through a weather sealed door in the loft. The main cabin gable ends were complete in the last post when we finished installing the rafters.

NOTE: We not only installed the gable end wall studs, but also the top plate as well (remember this is what the lookouts rest upon).

Below you’ll see that the deck gable end wall is built directly in-line with the main cabin gable wall so that the exterior OSB will sit flush across the main cabin wall framing and the deck wall framing.

Deck-gable-Wall-End-In-line-With-Main-Cabin-gable-all-end

We constructed the roof ladder in sections for ease. We first cut the lookouts to the predetermined length which meet our overhang requirements. Then, with the lookouts placed on top of the top of the gable end plate and nailed them into place with our trusty DeWalt cordless nail gun.