Welcome to Casual Craftsman! I document my adventures in travel, style, and food. Hope you have a nice stay!

Kids Treehouse Plan - Part Four

Kids Treehouse Plan - Part Four

Framing Treehouse Walls and Roof

I hope you enjoyed relaxing on your kids treehouse deck and are now ready to start framing walls for the treehouse, building the roof structure and attaching the siding and roof materials.  If you need to catch up on how we got to this point, check out the treehouse design process, site preparation and the treehouse deck posts on our site.

Here is what you will need in order to complete this step of the backyard treehouse:

Suggested Tools:

  • Saw
  • Cordless drill/driver or nail gun
  • Measuring tape
  • Speed square
  • Pencil or marker
  • Safety googles and gloves

Recommended Supplies:

  • 18 - 2x4x8'.  You need enough 2x4’s to frame all four walls and the roof structure.
  • 50 - 1/2”x6”x6’ fence pickets.  These will be used for our siding and roofing material.
  • 3” deck screws or equivalent nails - I like square or star drive screw heads over a standard phillips head because they do not strip nearly as easily.  Hopefully you have enough leftover from the deck build but if not, you should not need quite as many as before.
  • 2” deck screws or equivalent nails - These will be used for attaching the siding and roofing.
  • 12 - Hurricane ties for rafter hangars.  8d nails or #9 x 1.5 strong drive
  • 2 - Hurricane ties for ridge posts.
  • 1 Box of #9 x 1.5” Strong Drive Screws for hurricane ties
  • 8d nails as an alternate to the strong drive screws above

Step 1 - Frame the walls

- Basic Wall Framing

Let’s get started framing the treehouse walls.  Hopefully, you have followed my previous steps and have drawn out some plans that detail the height and width of each of your walls.  If so, measure and mark the length of your top plate on your first 2x4 and cut it to the appropriate size.  Use the top plate as a guide to mark and cut the bottom plate ensuring that both the top plate and bottom plate are the same length.  Refer to your plans for the height of the framed wall.  When you measure the 2x4 to create your studs, you will mark it three inches shorter than the total planned height of your wall.  This is because the stud will sit between the top and bottom plates and each plate measures 1-1/2” thick.  So, if you planned your walls to be 60” high, cut your studs 57” because they will sit on the bottom plate which is already 1-1/2” off the deck and when the top plate is attached it will add another 1-1/2” to the overall height.  After cutting the first stud, use it as a guide to cut the remaining studs.  Make note that there should be a stud on the end of each wall and that all other studs should be spaced 16” on center.  Place your top and bottom plates on a flat surface separated by about the same distance as the length of your studs.  Place the first end stud between the plates and drive your framing nails or screws from the top plate and into the top of the stud.  Adjust the bottom plate and stud so they line up and attach them by driving the screws or nails from the bottom plate into the bottom of the stud.  Add a stud to the other end of the plates and attach it as well.  Once both end studs are attached, use the 3-4-5 method to confirm squareness and make the necessary adjustments before adding the remaining studs.

- Framing for a window

If your wall will have a window opening, be sure that the window has a stud on either side of the opening.  This may require you to add a stud or two to your wall, adjust the spacing of your studs slightly or adjust the width of your window opening so that it is properly framed.  My backyard treehouse design does not have a glass window installed.  All I did was frame an opening and was not interested in installing actual window.  If you want an actual window in your treehouse design, be absolutely sure to frame it according to the specifications of the window you plan to install as this will ensure a good fit and give you the option to buy a window off the shelf rather than having to buy custom sized windows.  To properly frame each window opening in your treehouse wall, you will need to cut 2x4’s for a window header, sill, cripples and trimmers.  The header will form the top support of the window and is supported by a trimmer on either side.  The cripples are like studs that are cut to the length equal to the distance from the bottom of the top plate of the wall to the top of the window header.  Cripples will also need to be cut to the length equal to the distance between the top of the bottom plate and the bottom of the window sill.  All of these pieces will be attached using the same screws or nails you are already using to frame the rest of the wall.

 framing a window
 kids treehouse framing

- Framing the door

For the wall that has a door, it will be framed similarly to the window.  The door will need to be framed between two studs so if you need to add a stud, go ahead and do so.  The door will have a header, trimmers on either side and cripples across the top.  Be sure to cut the bottom plate so that it does not cross through the door opening and create a tripping hazard.  In the wall frame containing the door, the bottom plate will be cut into two separate pieces where the gap between the pieces is equal to the width of the door.  My treehouse plans call for an open door frame and I never install an actual door.  If you plan to purchase a door, be sure to frame your opening according to the door manufacturers specifications.

Step 2 - Attach walls to deck

Once you have your four walls completely framed you can start attaching them to the treehouse deck to create the house enclosure.  Depending on the size of your walls, you may need help lifting them into place.  Place your first wall frame onto the treehouse deck making sure that the wall is straight and there is equal space between the bottom plate and the edge of the deck.  Attach the frame to the deck using two framing nails or screws on each end followed by two screws/nails between every other stud.  Place the second wall frame in place and be sure that it is straight and square.  Use the 3-4-5 method again in order to confirm that the second wall is square.  Attach the frame to the treehouse deck and to the first wall using screws/nails.  Following the same procedures, add and attach the remaining walls.

Step 3 - Frame the Roof

If you have never built a roof before, I would suggest checking out a couple of these resources first in order to learn about pitch, rafters, ridge boards and bird mouth cuts.  Do not be intimidated though because it really is not too hard I just thought you should have some background before we get started.  

- Build ridge board supports

The first step is to build the ridge board supports.  Each support is made with three pieces of 2x4’s.  The first two pieces will be cut to the same length and the third piece will be cut 3-1/2” shorter so that when your 2x4 ridge board is placed inside the support, the top of the ridge board is even with the tops of the side supports.  Secure the three 2x4’s together with the shorter board sandwiched between the longer pieces using nails or screws.  Create another support with the exact same dimensions and secure those pieces together as well.  Find the center of the top plate on the first wall that will support your roof and mark this spot.  You will then place the first ridge board support centered on this mark and attach it to the top plate using hurricane ties and the appropriate screws.  Mark the top plate directly across from the first support and attach the ridge board support to the top plate with hurricane ties and screws.  Measure from the outside edge of one support to the outside edge of the other support and transfer that measurement to a new 2x4.  Cut this 2x4 to size, slide it in the ridge board supports and secure it with screws.  You now have your ridge board firmly in place and are ready to start making your rafters.

 treehouse ridge board

- Cut the rafters

Rafters need to be cut at proper angles in order to attach flush to the ridge board and the top plate of the walls.  I highly recommend you read this source (http://www.thisiscarpentry.com/2012/11/09/common-rafter-framing/) and watch the corresponding video in order to learn more before proceeding with this step.  These guys do a really good job at explaining the process and build a small mock up along the way that is exactly what you will be doing here.  Measuring, calculating and cutting the rafter angles takes some practice so do not get discouraged.  Keep in mind that once you get one right, you now have a jig by which you can create all the other rafters.  So spend some time getting the first one right and all the rest will be easy.

- Attach rafters to ridge board

Now that you have your first rafter cut, you will need to attach a hurricane tie to the ridge board where the rafter will contact it.  Attach the hurricane tie to the ridge board with the appropriate screws and then set your rafter inside the tie and along the top plate.  Add a second hurricane tie to the top plate and place the rafter inside of it.  Secure the rafter to the hurricane ties with the correct screws at both the ridge board and top plate hurricane ties.  Continue attaching all the rafters using the same process and spacing the rafters 16” or 24” on center being sure to attach the rafters to both ends first and then filling in the middle.

 treehouse rafter construction
 treehouse rafter hurricane tie

Step 4 - Attach wall siding

Step back and admire your fully framed backyard treehouse.  Your kids are probably getting really excited now that they can actually see the physical treehouse coming together.  We need to start attaching the siding and roofing material now.  In my treehouse design, I used 1/2”x6”x6’ dog eared fence pickets for both the siding and roofing.  As I have mentioned before, this is an area where you can get really creative and sculpt the look and feel of the treehouse you wanted.  The fence pickets I used are inexpensive and work just fine.  However, they will not keep your treehouse dry during a heavy rain, they will not provide much insulation from the cold if that is a factor for you and they may not represent the look you want.  You have many options for siding and roofing material and I encourage you to put some thought and consideration into these options so that your kids end up with the treehouse they have been dreaming about.

 treehouse siding

I would cut off the dog eared portion of every picket so that both ends were square and then attach the pickets to the studs with screws starting from the bottom of the wall and working my way up.  Since you need to attach the picket to each stud with two screws or nails, if you have a framing nail gun or finish nail gun, attaching the pickets will be a lot faster than screwing them on.  Make sure that the first picket is completely level before attaching it because any variance will cause bigger problems as you proceed.  Check your levelness often throughout this step.  If the pickets were not long enough to cover the entire side, I made sure to cut them to a length where they would begin and end on a stud and would then stagger them as I continued up the wall so that there was not a long running seem in any one spot.  Also, I did not overlap my pickets on the walls although I could have and it would have probably looked nice and would have kept the inside of the treehouse drier during heavy rains.  One more item to note is that I did not cover the inside of my treehouse with anything as I just left the framing exposed.  I would suggest finishing the inside of the walls as it will really spruce up the look of the treehouse and help keep it warmer and drier.  

Step 5 - Attach roof material

I attached the pickets to the roof starting from the bottom and working my way to the top being sure that the pickets were straight and that I overlapped each one by a few inches to allow the rain to run off of them.  Screw or nail the pickets into each rafter with two nails at every connection point.  Keep in mind that using fence pickets for your only roof material will not keep the inside of your treehouse completely dry especially during a heavy rain.  If you want a completely dried in treehouse you will need to add additional or alternate materials to your roof.  When you get to the top of the roof, you will want to lay one picket flat on top of the ridge board so that it also overlaps the top pickets on either side.  This will seal up the roof ridge gap and prevent rain from coming straight in.

 treehouse roofing material

Step 6 - Get the kids

This concludes part four of our backyard treehouse build.  You have put in a lot of effort to this point and you are on the downhill side of this project.  So, go grab your kids and let them give their new treehouse a good walk through.  We are going to start preparing the final stage of the backyard treehouse plans.  In part five, we will finish up the entire project by adding railings and stairs and then we will put the finishing touches on with paint and stains.

Kids Treehouse Plan - Part Three

Kids Treehouse Plan - Part Three