Hip Roof Framing Plans - Designs and Illustrations

Equal pitch hip roof framing plans showing basic hip framing layout and placement of common rafters and hip roof rafters by custom house plan designer.

In this article we will try to show you how to build a simple "hip roof" and try and show the component parts that make up an "equal pitch hip roof" structure using the "double cheek cut hip rafter method" used by most framers today.

In this method of construction the center ridge board will grow by half the thickness of the ridge board material, usually 3/4" at each end of the structure.

In this example we are looking down on the right rear corner of a simple rectangular building. Using half the span distance of the building less half the ridge board thickness which is 3/4" in this example, mark your top plate and set ahead 1 1/2". That will be the location of the first common rafter front and rear on both ends of the building.

Your jack rafters will start from that position and layout on 16" centers toward the right rear corner. This is the hip and jack rafter measurements as shown in this example. You could actually cut all four hip sections from these measurements and they would complete your rafter construction perfectly.

But that would not work well for ceiling joist layout and being able to tie both rafters (common and Jacks) together to create a solid and well built home. So we would want to offset the common and jack rafters 1 1/2" to allow both to be able to lap beside each other and be nailed together forming a well built roof system.

This method will cause all of the rafters and jack rafters on the front side to maintain a 16" on center balance.

This makes cutting the roof sheathing much easier and quicker. In the event the ceiling joist are used as a attic flooring your plywood sheathing will work well also.

Note: This will force you to custom cut the front right corner as well as the front and rear sections on the left end of the building. I show this in figure #4 marked "Special Cut Jack Rafter Layout" near the bottom of the page.

Not to worry though its easy to do. The right front section jacks would simply be 1 1/2" shorter. The left end can be simply measured once your layout work is complete maintaining your 16" on center the entire width of the building. The remaining jack rafters in these two sections would simply decrease each one by a given number according to the roof pitch used.

Common Rafters:
Common rafters are the same on gable roofs as well as on hip roofs and can be figured exactly the same way.

Hip Corners:
Regular pitch hip roofs means that all four sides are on the same angle plane and will run at a 45 degree angle directly from the corner to the end of the center ridge board.

Hip Rafters:
Hip roof rafters are designed with a lower pitch so the corner can be made and roof sheathing can be applied to form the corner of the structure properly. It also carries the smaller jack rafters.

Plan View:
Our plan detail drawing shows all four corners of this simple hip roof structure with all common rafters, hips and jack rafters fitting together properly.

Equal Pitch Roof Rafter Layout:
Placing the ridge and common rafters should be the first thing to be laid out on your wall top plates. From this layout you can mark out all the rest of the common and jack rafter positions. It might be a good idea to draw a big X where the rafters will actually set.

Hip Rafter Side Cut Angles:
This side cut angle can be obtained the same way as the jack rafter cheek cut angle.

Jack Rafter Side Cut Angles:
Side cut angles or commonly called cheek cuts enable the jack rafter to connect properly with the side of the hip rafter.

Plywood Cut Angles:
Even though a equal pitch hip roof has hips running inward at a 45 degree angle the plywood sheathing cut angle is very different and on our 4x12 pitch roof example it turns out to be 46.53 degrees.

Jack Rafters:
Jack rafters start with the first common rafter and continue on to make up the complete corner. These must be calculated properly to fit in order for the sheathing to continue to the corner. When installing your jack rafters be sure to straighten the hip rafter and install the first two jack rafters some where in the middle to secure the hip. When you install one side install the other side of the hip as well. This will help keep the hip rafter nice and straight.

Typical Ceiling Joist Layout:
Ceiling joist layout if placed properly will enable you to set all rafters much quicker and finish with a very neat project.

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Building Process Video 21: Second Floor Framing

We stand up the walls of the second floor and prepare to set trusses on our Las Vegas building project.

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Home Building Mistakes - Incorrect Window Header Framing

hometips.gregvan.com Click on This Link for some interesting articles about almost everything related to homes and construction. Watch this video to learn more about problems framing carpenters make when they're in a hurry and don't take the time to double check their measurements or wall layout. I don't know how many times someone tells me how easy it is to build a home, until they actually do it. Just because someone else makes their job look easy, doesn't mean that it actually is. Experience construction workers realize and avoid common mistakes like these. Don't forget to visit our other websites and keep watching our videos.

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Wood Framing For Your Home Projects

There are at least a million different things that can be discussed about framing. I will try here to cover the basic framing items you will encounter whenever you are building a shed or garage and some items in a house. It is strongly suggested you do NOT try and frame a house on your first outing. A house is a major undertaking and is best left to the pros. A shed, garage or a gazebo or other landscape feature is well within the average handyman's ability. If you have basic carpentry tools you should be able with care, build a solid long lasting structure. There are many pre-made plan sets available at your local lumberyard or big box store. They will provide a good layout, perhaps furnish lumber quantities needed for the job and are a good guide for you to follow. Remember you should always check with your local building department to inquire as to whether a permit is required or not. Many municipalities do not require permits for shed, decks and pools but do require them for garages, etc. It is always better to ask first.

Tools needed: Safety glasses, power saw with sharp blade, good hand saw, hammer, 4 foot level, square, string line, pencils, chalk line, tripod and level (available for rent at your local rental store by the day for only a few dollars), extension cords or other power source and a good tape measure.

Materials: Look at your drawings to see if a lumber list is printed on them. If it is, you may take it to your lumber yard and they will price all the materials for you. Don't forget nails or screws. If there is no lumber list and you cannot figure out the materials you need, many stores will when they are not so busy, figure the lumber for you in order to make the sale. Ask the salesperson. Most will be happy it do it for you.

Hopefully you own a set of saw horses to use as a cutting table. They are not critical but if you can afford them or can build them they will save your back a great deal of pain. Look at your plans. Study them. Select the lumber you need for the floor framing and lay it out on the saw horses. If you're building a garage do the same for the wall framing. The plans will show you what lengths to cut the floor pieces or wall studs. Your footings or foundation walls should be in place by now. Frame the perimeter band or "rim" joists first. This will allow you to make sure the building floor is square and level. Using your tape measure, measure from one outside corner across to the opposite outside corner and record the measurement. Lets say it is 110 ½". Now measure across the other two opposite corners. If you get a measurement of 110" even, you are 1/4" out of square. It's ½ of whatever the difference in your measurements are. Just move the corners a little bit until both measurements are 110 ¼". Your floor frame is now dead square. Don't be upset if you find you're out of square.

Nobody gets it perfect on the first try. If you have made accurate cuts in your lumber and the lengths are correct, you will find it is easy to make the unit square. You now have a 4 sided perimeter rim joist box completed. Start to fill in the floor joists on the centers shown on your drawings. Do not change the dimensions. They are drawn that way for a purpose. It is for structural support but you will find when you go to install your plywood flooring it will not fit in standard 4' x 8' sheets. Plywood comes in 48" widths so if you alter your floor joist spacing, the plywood will not fit and you will end up lots of cutting to do and result in a huge waste of material. So, we now have a complete floor framing system. Install any hangers shown on the drawing, wood blocking or other components shown on the drawings. It is time to install the plywood. Here's where the good long lasting sheds begin and others fail. Take the time to use a good quality construction adhesive on top of each joist before you install your plywood. Using an inexpensive caulk gun, apply a bead along the full length of the joists you are about to cover. Lay your plywood carefully on the joists so as not to spread the adhesive all over the plywood and you! Now nail or screw down the plywood. A general rule of thumb is space your fasteners 8" apart along the perimeter of the plywood and 4-6" apart on the "field" or inside of the plywood. This will provide a super strong and squeak free floor. Continue on until all the plywood flooring is complete.

Now for the wall framing. You have a great place to frame your walls on the floor you just finished! Just layout the stud and plate material on the floor for one wall. Place the bottom plate wood closest to the edge of the floor or bottom of the wall, layout the studs roughly where they go and then the two top plate materials across them. Assemble the wall according to your plans. If there is a window or door in that wall, frame for it now. It's a lot easier when the wall is laying flat on the floor then when it is standing upright. Measure across the corners again, the same as you did on the floor frame. Make sure the wall is square. Now apply your plywood. Leave the plywood hang down over the lower plate at least a couple of inches. You will see why later. Yes, while it's laying flat. It is not necessary to cut out the windows or doors, they can be cut out later. OK, the first wall is framed and covered with plywood or "sheathed". Its time to stand it up into place.

Hopefully you have some help around. It's not impossible to do alone but it's a lot easier with help. If you have help, just stand the wall upright and using your sledge hammer and with at least one person balancing the wall, knock it into place along the edge of the floor frame. When you finally get the wall to the edge, the extra plywood hanging down over the lower plate will drop off the edge. Push the wall tightly against the lower floor farming and nail the plywood to the floor frame. Now quickly as the other person is still holding the wall, take a 2 x4 and nail it to the end stud of the wall about ¾ of the way up the wall until it is finally nailed into place. Take the other end and nail it to the floor or rim joist on a 45 degree angle. This will help hold the wall until it is securely nailed and other walls are in place. There are commercial wall jacks that can be purchased or rented that will not only jack up the wall but will hold it until final nailing. Great tool! Now nail the new lower wall plate securely to the rim joist making sure the wall is even on the ends and not sticking over one way over the other. It is time to frame your 2nd wall.

When the 2nd wall is completely framed and sheathed, again slide it into place with one end matching one end of the first wall. Using the sledge hammer and with your partner balancing the wall upright, make sure the corners are tight together. Once they are, nail the corner 2 x 4's together making up the corner. Nail the sheathing to the bottom rim joist again. The walls along with the brace should stand on their own at this point. Now frame the 3rd and 4th walls and install them the same way as the first two always checking with your 4' level to assure the walls are plumb before you nail them to the floor and each other. Once all 4 walls are erected, plumbed and nailed, you may want to place some 2x4's across the walls to further brace the structure while you frame the roof. Make a note here that we are using 2x4's for our walls but the framing sequence is the same whether your walls are 2x4, 2x6 or whatever is called for on the plans. It is time to install your top plate. This will be a 2nd set of 2x4's running around the tops of your walls tying them together. The first 2x4 starts on the end of the corner wall and runs across to end of the 2nd wall This ties the corners together. Each subsequent 2x4 does the same thing. It is not necessary for these to be one piece but it helps. Each 2x4 "laps" onto the wall before it. When you are done, the top plate will be a double layer or 2-2x4's thick. This provides the added strength for your rafters to sit upon.

Headers-Over every wall opening either for a door or window perhaps, it is required to strengthen the wall where the studs have been cut away. Your plans will call for 2-2"x6"s perhaps. Cut the 2" x 6" the length of the rough opening plus 3". Your window size rough opening, say is 30" wide and 40" high. You need to cut the 2 x6's 33" long. Your wall studs will also be 33" apart running from floor plate to top plate. Measure up from the floor to where the top of window will be above the floor. Mark your studs. Now install the header with the bottom of the header on that mark. Nail it securely through the sides of both studs. Now cut 2 more 2 x4's that will be installed as "jack" studs. Install these jack studs directly under the ends of the header and nail them to the full height studs. Your finished rough opening should be 30" wide. Many framers will install the jack studs first and then simply lay the header on top and nail into place. Now cut a 2x4, 30" long. Measure down from the bottom of your finished header 40" and mark the jack studs. Toe nail this bottom window sill plate into place. Your rough opening is now 30" x 40". Infill under the bottom window sill with 3 pieces of 2x4, one under each end and one in the middle where it will fall at the 16"OC wall stud layout. This will help later if drywall or other wall finish is to be installed. Repeat for any other wall openings that were not framed during wall construction.

Roof Framing- There are many types of roofs that may be used on buildings today. Common types are gable roof, shed, mansard, barn or hip roof. Most sheds or garages use a simple gable roofing system. Do not be afraid to try the others, just follow your plans carefully. Layout the materials for your rafters. Each rafter will have a cut at the top to match the ridge board and another set of cuts at the bottom called a "birds mouth" for where the rafter sits on the top plate and another vertical tail cut which provides the vertical face for you to nail your fascia boards against. Rafter cutting can be tricky. Most plans provide a rafter cut template which makes the job real easy. Your plans will tell you what overall length to cut the rafter, what angle the top must be cut and the shape of the birds mouth. MEASURE TWICE, CUT ONCE! Cut your ridge board to length. The ridge board will also be one size larger than your rafter. 2x6 rafter, 2 x 8 ridge board. Place the ridge board across the wall top plate and then cut two 2x4 to support it. A little math here. If your ridge board shows it is 10' above the floor and your walls are 8' high, and your ridge board is 2x8, deduct 7 5/8" (nominal size don't forget) from 10' leaving 9'-4 3/8". Deduct 8' walls from this answer and we get a piece needed of 1'-4 3/8". Cut your 2 x4's this length. Placing one 2x4 under each end of the ridge board, nail the 2x4 to the top plate and to the ridge board. The ridge board is now temporarily supported on each end by this short stud.

Now test fit the first rafter you cut. It should sit snugly on the top plate and lay flat against the ridge board with no spaces. As the weight of the roof load is applied, (plywood, shingles, snow perhaps?) it will push down on the rafters against the ridge board. If there is a space between the rafter end and the ridge it will not work correctly. Check the birds mouth cut on top of the wall. Does it fit snugly? Now is the time to adjust. If everything fits well, clearly mark your rafter TEMPLATE and do not use it UNTIL THE END. You will use this rafter to cut all the other rafters without having to measure each one. Ok, now cut all your rafters on your sawhorses using your rafter template for layout lines. Just trace it. Take all the rafters into the shed and lean them against the top of the wall approximately where they will be installed. You will appreciate this if you're working alone. Using a sturdy ladder, place your first rafter against the ridge board and nail it to the top plate on the wall. Now install the opposite rafter on the other side of the ridge board. Start on the end rafters first. Now do the two rafters on the opposite end of the shed. You will see this stabilizes the ridge board. Now take a few minutes to make sure everything is straight and plumb. Make sure your ridge board is level and not bowed. If everything is correct, go ahead and install the balance of the rafters using the TEMPLATE as the last rafter. Make sure all rafters are nailed properly.

Roof sheathing-Using the plywood thickness specified in your plans, start installing the roof sheathing. Depending on the shed size, a full sheet can almost always be placed at the bottom starting in one corner. NOTE: Before you start installing the plywood, tack nail your fascia board to the vertical end cut of your rafter. Using a scrap piece of wood, hold the scarp on top of the rafter sticking over the end. Slide the fascia board up against the scrap and nail. You will see the fascia dos not come all the way to the top of the rafter tail. When you install the roof sheathing, you want the plywood to hang over the rafter tail and end at the fascia board. Install your roof sheathing and nail it completely to the rafters. You want to leave a small opening at the top of the rafters perhaps 2-3" wide on each side of the roof. This will allow hot air to escape out the roof and keep your roof cooler. Install all your fascia boards.

Roofing-There are also many types of roofing available today. Most common are fiberglass shingles but wood shingles, metal roofing and rubber membrane roofing are being used much more often today. Assuming you are using fiberglass shingles you need to figure how much you need. The simplest way to measure your roof. If the roof is 8' x 8' on each side, that's 64 square feet each or a total of 128 square feet. Most shingles come 3 bundles to a square. 128 equals 1.3 square or 4 bundles of shingles. You will need some shingles for cuts and roof ridge caps. Buy 6 bundles. Shingles come in many colors today and some shingles come 4 bundles to a square. Check the packaging. You will need enough aluminum drip edge to go all around the perimeter edge of the roof. Measure it. They come in full 10' pieces only but also come in varied colors. Felt or tar paper. Many contractors today do not install felt paper but I still think you get a much better job it you use it and it's cheap. It provides a 2nd layer of roof protection in case of damaged or missing shingle. If your heating the shed or garage it is strongly suggested and required today in most states that you install ice and water shield membrane. It comes in various widths and roll sizes. You want to install a minimum of 2 widths starting at the lower edge of your roof. It is sticky and tricky to install but is well worth it. It prevents ice dam build up at the eave edges from the re-freezing of water melted from the heated portion of the roof and the unheated soffit area hanging outside your wall.

Install your drip edge holding it tightly against the fascia board and nailing it down through the roof sheathing. This is a finished piece you will see later under the edge of the shingles and helps prevent shingle edge damage. There are so many types of shingles available it is impossible to describe them all here. Follow the directions on the shingle bundles. Work you way up the roof from one side making sure you keep the shingle tab slots straight with one another. Cuts for one end can be used on the other and so on. You will have some scrap left over. Keep them for now. After your drip edge is installed, you must install one row of shingles upside down along the bottom edges of the roof. This will provide a water seal when the first shingle is installed directly over the upside down shingle and you will see the same color underneath the all the tab slots.

With all the shingles installed it is time to install the ridge vent and cap shingles. Make sure your roof shingles do not cover the slot you left in the roof sheathing. If they do, trim them back now. Continuous ridge vents come in many sizes and shapes as well. Some are pre-formed paper, wire mesh, cellulose and many others. They all serve the same function. You carefully bend the vent in half and place it along the top of the ridge board over the opening you left in the plywood. Place a few roofing nails as you go holding it into place. Stop each end of the ridge vent about 8" from the ends of the ridge board. Now gather all your leftover and cut shingles. You want to cut the full tab off the shingle to make ridge cap shingles.

Shingles are cut into tabs of 1/3 shingle each. Use 2 nails on each cap shingle lapping each shingle so nails do not show. Place a small amount of roofing tar under first shingle to hold it down so you will not see exposed nails and to prevent wind ftom lifting the first edge. Install the ridge cap shingles end to end. Face the shingle ends away from the prevailing winds. If it is a large roof, you may install one-half from each end and end in the middle of the roof. You then cut one smaller tab to use as a closure piece the same color as your shingles and nail all 4 corners. Place a small dab of roofing cement on each nail to prevent water from entering into the nail hole. Basically your shed or garage is done. Install the door hardware, windows and trims if you have any. A good coat of paint and your ready to go! All the dimensions I have provided here are samples and are provided as a guide only. Please double check all your dimensions before cutting your lumber and remember to always wear safety glasses when using power equipment.

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Design of Roof Truss Layout and Correct Framing Drawings

Roof trusses are widely used in residential and wood framed commercial projects. A roof truss is usually cost-effective and quick in construction than a roof framed with rafters. A roof truss is crafted from small pieces of lumber; it is then fabricated in a shop and after that set up at the site.

When we start designing a house we first create a truss layout which shows places where trusses will be fit in the roof, anticipated shapes of the top & bottom of the truss, plate heights and estimation of load on the trusses. The builder then gives this layout to its truss supplier. The truss supplier prepares actual design of each individual truss according to our roof design layout. The truss supplier may propose some modifications in the design because they have slightly different preferences to construct the truss using available proprietary software and CAD tools. Truss drawings as prepared by the truss supplier are then sent to the Architect for a review.

The architect forwards these drawings to a truss engineer who further examines various parameters such as the size of home, dead/live loads based on geometry, required truss span and roof pitches and give final go ahead for fabrication. The completed truss drawings show precise placement of trusses in the roof structure and precise inter-relation of truss members.

A truss is normally designed to transmit dead and live loads to other members in the structure. With regards to new home construction, a dead load is the burden of static components like the truss itself, roof beams, roofing materials, sheathing and ceiling material. A live load is dynamic in nature, such as wind, snow, furniture, movable loads, etc. Trusses are crafted to prevent flexing and bending and are usually tied together with tooth like metal plates made from galvanized steel or metal.

The common truss contains parallel sides so as to have a nearly same pitch on both sides of a center point. A lot depends on the interior ceiling design and roof pitches of your home when designing a layout for roof truss. Roof truss design allows flexibility to change the interior space as the truss normally be placed on an outside wall, leaving the interior space free for you to design and decorate accordingly. Trusses come in a wide range of designs giving you a creative freedom to change the ceiling design!

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Framing a Gable Roof

There are many styles of homes that are built with gable roofs. It is the simplest roof of all to frame. It is also the most common roof built for that reason alone.

All the rafters cut for a gable roof are all cut to the same length. The birdsmouth, which is the cutout that sits on the top plate, is located in the same place on all rafters. The overhang, if there is one, is also the same.

The ridge board, which is usually a 2x, runs the full length of the house. This can be cut ahead of time and have the rafter layout marked on it. The rafter layout usually matches the wall stud layout. This transfers the roof load down to the foundation.

Before any framing begins, some of the plywood that will be used for roof sheathing is laid across the ceiling joists the whole length of the building. This gives the carpentry crew something to comfortably stand and walk on during the construction of the roof. It's also a good idea to pass all the roof plywood up to the ceiling joists. This makes passing it up to the roof much easier.

Next, pass the ridge board(s) up and lay them on the plywood walkway, making sure the layout is going the right way and matches the wall layout. Now pass the rafters up. Lay them with the plumb cuts on the plywood and the tails on the top plate. If the house is a ranch, the rafters can be leaned against the wall between ceiling joists to keep them from sliding of the wall. Send up a couple of 2x4's for bracing and you are ready to frame.

Before the ridge board is even raised, nail two rafters to one side, nailing on the first one and the last one on the layout. The ridge can now be raised. Pull the ridge so the birdsmouths are tight to the wall and raise it high enough so the level cuts of the birdsmouths are flat on top of the wall. Once the rafters are in place tack them to the wall. Now nail two rafters on the other side of the building to the top plate. These will also be the first and last rafters on the layout and will mirror the ones you put up on the other side of the building. Raise or lower the ridge so the top of the plumb cuts on the rafters meet the top edge of the ridge. If the rafters where cut correctly,
the plumb cuts should fit snugly against the ridge with little or no gaps.

With the ridge in place, install a stud in the gable end from the ridge down to the top plate, using a level to plumb it up. Take one of the 2x4 braces and nail it near the top of the stud. Nail a block to the plywood walkway being sure to catch a couple ceiling joists. Now put the level on the 1 1/2" side of the stud and plumb it that way. When the stud is plumb, nail the 2x brace to the block. This will square up and position the roof where it needs to be. The rest of the rafters can now be installed, alternating from one side to the other, pulling the rafters tight to the wall and bringing the plumb cut to the top of the ridge. By alternating from one side to the other the ridge will stay straight. If one side is installed all at once, the weight will push on the ridge creating a bow. This will make it tough to straighten when the other side is put on.

After the roof is framed, collar ties, fascia boards, and overhangs are put on. With those items in place, the plywood can be put on. Frame in the gable ends and your ready for shingles.

Mike Merisko (c) 2006
http://www.sawkerfs.com

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Pat's New Garage - Part 1: Framing

Pat's getting a new garage/workspace! This is first in a series of shorts on it's construction and finishing. Stay tuned for more!



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Balloon Framing Gable Walls

Prior to the 1950's balloon framing of new homes was the standard construction method, until the advent of platform framing. Platform framing is a safer, quicker, and more cost effective method than balloon framing. With that being said, balloon framing still has many effective uses in modern house framing that can be incorporated with platform framing for a safer, sturdier, and more cost effective home.

Balloon framing originated in Chicago in the early 1830's and replaced the prior construction method of mortise and tenon. The name originated from the old mortise and tenon carpenters when they first saw the framing method in use. With the long skinny framing members being utilized and held together with only nails, they thought it would probably be blown away with the next strong gust of wind just like a balloon. The name caught on and has endured to this day.

Disadvantages

Balloon framed gable walls are very tall, usually eighteen feet or more above the floor level. This added height requires the use of scaffolding for the framing carpenters, electrician, plumber, heating ventilation and air conditioning, insulator, drywall installer, painter, and trim carpenter resulting in higher labor costs.
Fire can travel up the stud bay just like in a chimney, to mitigate the risk of fire, blocking should be installed at each ceiling and floor level.
The required use of longer studs increases the cost per lineal foot resulting in still higher expenditures.
These walls can be very heavy and dangerous, even life threatening, to raise requiring the use of proper lifting equipment and highly trained personnel. The hazards of manually lifting balloon framed walls has been clearly defined by OSHA.

Advantages

The longer studs resist wind loads better and help to reduce drywall cracking and nail pops.
Very large windows with rounded, arched, or angled tops can be installed to enhance the aesthetic appeal of the home.
Ability to construct a tall chimney.
Two story open foyer.
Great room.

When considering the use of balloon framing to enhance the look and livability of your new home the advantages and disadvantages should be weighed carefully.

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