I'm a little confused about the Victoria Plans. I see that some people build these plans with large beams connecting to smaller beams (between the first and second floor) instead of the regular floors joists (running perpendicular to the long wall).
Do the plans include both the floor joist or beam option?
Also, is the Victoria always balloon framed?
Is 16' as wide as you can go?
Yes, the Victoria Cottage plan has balloon framed 2x6 walls with a ridge beam supported roof and a beam and deck loft floor system. It is not designed to be made wider without structural recalculation of the beams. Because of its more fixed beam layouts the Victoria is not as inherently flexible in its layout as the 20' wide plans.
That said, several folks have modified the plan and adapted it to their site conditions without great expense as modifications and new beam sizes can sometimes be done by the local lumber yard or a local builder.
So if I want a plan with 1.5 or 2 stories and conventional rafters (no beams) I need to go with the 20 X 30 plans?
I feel like I've seen so many threads here where it seems that the building resembles the Victoria (16' or so wide, balloon framed etc) that don't have beamed cielings or a ridge beam. What plan are they usiing?
Could you point to some with a link?
What is it you would like to have upstairs? A loft, an entire upper floor, or a cathedral ceiling?
In a 16 wide stairs take up a lot of space if built to code requirements. Is code involved for permitting?
I'll look for some links.
I'm looking to have a usable second floor. No loft, no cathedral.
Having built a small cottage before, I know the challenges of raising walls on the second floor of a platform framed structure when working alone. That's why the balloon framing technique appeals to me.
I guess both the Victoria and the 20 X 30 1.5 story both have balloon framing? I'd probably want to go with a 12 ft side wall on the balloon frame, but not sure if you can do that with a 20' width, although I know you can with 16' (again no cathedral).
You can do 12' balloon framed sidewalls if you will have a full loft. That ties the two walls together.
Talk to a local truss company. Explain what you want; see what they can make
Since I'm gonna be working alone, I was trying to stay away from trusses. I think it would be easier to use stick frame the roof with collar ties.
I should get a price on the trusses just to see how much they cost. I can't imagine how I would move them alone though.
Questions
Building permits, inspections required?
Where will this be built? Snow loads, hurricanes, seismic?
Do you have a foundation preference?
Roof pitch preference?
Yes, there are building permits req.
Located in upstate NY. Not sure what the snow load is, but I don't think it is extreme. 90 miles from NYC, so it's nowhere near Buffalo or that region with it's heavy snows. It'll be in a much more moderate snow area. I was going to go with a 12/12 pitch.
http://publicecodes.citation.com/st/ny/st/b200v07/st_ny_st_b200v07_16_sec008_par001.htm
Snow loads NY by code.
Looks like my snow load is 40 psf.
My thoughts are that NY State will not permit upper walls of any height above the (upper) floor unless...
1) the roof structure is an engineered truss type, or
2) the roof uses a structural ridgebeam, or
3) there are rafter ties across the wall tops at each wall stud, or
4) the roof and walls are designed by an engineer and has the engineers stamp.
The only way to know for certain would be to inquire, probably at the local municipality or county level. I'm not sure how NYS is setup for that sort of thing. Someone else here may know better or be able to pass on their personal NYS experience.
If a full floor was not required upstairs a 1 1/2 story design, with the upper floor on the tops of the walls and rafters something like this could likely be easily passed and built.
(https://i139.photobucket.com/albums/q305/djmbucket/construction/20W-24Flr-small.jpg)
The upper floor extends over the walls by a couple feet on each side. That would require an engineered floor. The rafter to joists connection are further apart adding 4 feet to the usable upstairs width. Where I've drawn the 4 ft vertical kneewalls could be constructed. Insulation would be in the roof, ridge to eve, and the eve area also insulated. The space behind the kneewall could be storage.
If a full floor upstairs is wanted a true 2 story with rafters could be built as the upper floor ceiling would be also the rafter ties.
At least that is how I think the NYS regs will shake out. Check to be certain.
Thanks for the feedback guys.
Don, thanks for the input. How did you find that info?
What I stated in reply#12 was based on this section of the building code as used by NYS (and most other states, if not all)...
R802.3.1 Ceiling joist and rafter connections. Ceiling joists and rafters shall be nailed to each other in accordance with Table R802.5.1(9), and the rafter shall be nailed to the top wall plate in accordance with Table R602.3(1). Ceiling joists shall be continuous or securely joined in accordance with Table R802.5.1(9) where they meet over interior partitions and are nailed to adjacent rafters to provide a continuous tie across the building when such joists are parallel to the rafters.
Where ceiling joists are not connected to the rafters at the top wall plate, joists connected higher in the attic shall be installed as rafter ties, or rafter ties shall be installed to provide a continuous tie. Where ceiling joists are not parallel to rafters, rafter ties shall be installed. Rafter ties shall be a minimum of 2-inch by 4-inch (51 mm by 102 mm) (nominal), installed in accordance with the connection requirements in Table R802.5.1(9), or connections of equivalent capacities shall be provided. Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice.
Collar ties or ridge straps to resist wind uplift shall be connected in the upper third of the attic space in accordance with Table R602.3(1).
Collar ties shall be a minimum of 1-inch by 4-inch (25 mm by 102 mm) (nominal), spaced not more than 4 feet (1219 mm) on center.
That is all copied from the IRC they use... available here (http://publicecodes.citation.com/st/ny/st/b400v10/st_ny_st_b400v10_8_sec002_par015.htm) online.
Nowhere do they make mention of dropping the ceiling/floor. Rather they only address the issue of raising the rafter ties (to increase headroom for the floor below). Since the codes are used as being prescriptive, not having a mention does not usually work as argument to permit something that is not addressed. That though, is something an engineer could address, design and stamp, and that should be accepted by a building code official. There are site built truss plans included IIRC, with the 20 wide plans from John. Those would more than likely have to have a NYS enginner approve them. At least that is what I think. Once again the NYS building depts should be able to give the best advise.
I believe for all habitable spaces required headroom is 7ft, but it could be 7.5 ft. This is important because I believe there is a minum square footage of 70 ft at 7ft for habitable spaces too. This would have to be researched. It is difficult to do this with a 16 ft wide building with traditional code approved stairs that aren't a spiral staircase.
I have seen the examples that you are talking about with a 16' or more building with a loft and no rafter ties and only collar ties built by people on this site. Many times these are built in areas without codes, and I don't think they are to the original plan designs. While they may be acceptable, I don't think they are compliant with the ICC
I see that building up may be your concern. I sat down and did a complete spreadsheet comparison of the 20x30 single story and a 16x24 complete 2 story (not 1.5 story). According to my caculations even with the added foundation costs for upstate NY and roofing square footage they are almost identical in cost. I did find that a 600 sq. ft single story had more usuable square footage than a 750 sq. ft 2 story because of square footage loss to stairs. I don't know what kind of square footage you are shooting for.
What don described is what the language is in the building permit applications for Otsego county. "Trusses must be certified and stamped by a design professional." Check with your county.
R305.1 Minimum height. Habitable rooms, hallways, corridors, bathrooms, toilet rooms, laundry rooms and basements shall have a ceiling height of not less than 7 feet (2134 mm). The required height shall be measured from the finish floor to the lowest projection from the ceiling.
Exceptions:
1. Beams and girders spaced not less than 4 feet (1219 mm) on center may project not more than 6 inches (152 mm) below the required ceiling height.
2. Ceilings in basements without habitable spaces may project to within 6 feet, 8 inches (2032 mm) of the finished floor; and beams, girders, ducts or other obstructions may project to within 6 feet 4 inches (1931 mm) of the finished floor.
3. For rooms with sloped ceilings, at least 50 percent of the required floor area of the room must have a ceiling height of at least 7 feet (2134 mm) and no portion of the required floor area may have a ceiling height of less than 5 feet (1524 mm)..
I believe that can be interpreted to mean portions of the ceiling may have a height of less than 5 feet, but the square footage of that shorter area does not count towards any minimum room size.
There are also special considerations for bathrooms........
The code is a very handy thing to become familiar with when looking at designing from scratch or modifying plans.
For NY state you would be advised to have the truss company design, build and deliver trusses to the loft floor. A truss resolves all sideward forces internally and locks them into a stable configuration that only has downward forces. You don't have to be concerned about collar and rafter ties. Within reasonable limits you can also set the center ceiling height.
In the 20' wide 1-1/2 story plan I have truss diagrams that can be used to build a sturdy site-built truss (for non-code areas) or used as an outline shape for the local truss engineer (for code areas). These trusses sit on balloon framed walls with the loft floor joists resting on a ledger and nailed into each of the studs to provide extra stiffness in the wall. However, this is not needed to support the truss. You can platform frame the walls and as long as the truss resolves all forces downward you are not pushing outward on the walls.
You can see the framing system (using the site built truss) HERE (http://www.countryplans.com/mcelroy.html). I expect that the truss designed for you by the truss company will be considerably lighter that this one. You will probably still want some help on hand when building the roof.
Thanks Squirl, Don and John.
This thread has cleared up a lot of the confusion I've had.
I guess I just need to decide if I want to go 1.5 stories with stamped trusses or 2 stories stick built.
Quote from: John Raabe on February 24, 2011, 05:53:01 PM
In the 20' wide 1-1/2 story plan I have truss diagrams that can be used to build a sturdy site-built truss (for non-code areas) or used as an outline shape for the local truss engineer (for code areas). These trusses sit on balloon framed walls with the loft floor joists resting on a ledger and nailed into each of the studs to provide extra stiffness in the wall.
Got it.
Here is one of the pics I had in my memory (about a 1/3 of the way down the page). There are others but I haven't found them yet.
http://www.countryplans.com/20w_loft.html
I wish I was in one of those "no code areas". ;)
Archimedes:
Thanks for pointing me to that page. I have updated the image. I don't remember where that full span rafter image came from but it isn't per my plans and puts a lot of thrust on the walls. Collar ties (in top 1/3 of rafter) could help out there (and were probably put in) but these ties alone would not meet code in most places today. My 1-1/2 story plan has a truss roof framing plan rather than rafters and ties. Trusses resolve all the forces internally and do not have the same issues as rafter framing.
I apologize for any confusion.
http://www.countryplans.com/mcelroy.html for other pictures of the truss roof system.
The loft picture on the 20x30 page still appears to show collar ties rather than rafter ties -- i.e. the loft ceiling appears to be well more than 1/3 of the way up the rafters. Which suggests that the plan is not prescriptive as depicted. It seems that to meet code as MountainDon describes it with a 20-foot width, you'd need 12-foot balloon walls with the loft joists placed just high enough to give 7 feet of ceiling height on the first floor. Then the surface of your loft floor would be roughly at 8 feet, giving you 4-foot knee walls, which gives you just enough clearance to put your rafter ties at the top of the bottom 1/3 of the rafters (with a 12/12 roof) and have 7 feet of ceiling height in the loft. Is there something I'm missing?
The only other alternative for a habitable loft in IRC jurisdictions appears to be a ridge beam. R802.3.1 says "Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice." When it says "designed in accordance with accepted engineering practice," does that mean any plan using a structural ridge beam (in lieu of rafter ties) is not prescriptive and requires an engineer's stamp?
You've got it.
The "designed in accordance with accepted engineering practice" is truly the deep end of the pool. I've argued it with inspectors and have had both outcomes. The intent comes from old code which allowed me to design elements as long as I could provide the calcs showing I had done it correctly... according to accepted engineering practice. In other words saying I had always done it that way was not a valid argument, showing the rational design process was sufficient. Many states have now modified the interpretation of that statement to mean "designed by a registered design professional". So this is an area subject to interpretation. Many places will allow elements like ridgebeams and girders to be designed by the supplier who uses the software and engineering support of the manufacturer... usually LVL's etc. when my BO has requested, the supplier, usually a technician, has sent calcs back to the home office for review and provided stamped letters from their engineer back for that engineering support, good business. Go carefully here, they usually don't design the support conditions. Put a ridge over a tall thin wall and the ridge might support the roof until the wall buckles under it. I can see both sides of these debates.
Quote from: publius on February 25, 2011, 05:47:28 AM
The loft picture on the 20x30 page still appears to show collar ties rather than rafter ties -- i.e. the loft ceiling appears to be well more than 1/3 of the way up the rafters. Which suggests that the plan is not prescriptive as depicted. It seems that to meet code as MountainDon describes it with a 20-foot width, you'd need 12-foot balloon walls with the loft joists placed just high enough to give 7 feet of ceiling height on the first floor. Then the surface of your loft floor would be roughly at 8 feet, giving you 4-foot knee walls, which gives you just enough clearance to put your rafter ties at the top of the bottom 1/3 of the rafters (with a 12/12 roof) and have 7 feet of ceiling height in the loft. Is there something I'm missing?
I guess it is mathematically possible to do it that way, but then you'd have two floors with very low ceilings. I'm 6'1", so that's not a very appealing option.
I could platform frame the second floor and just use shorter walls (say 6' high) which would make it easier to work with alone. Then stick build the roof with rafter ties at 8', and collar ties in the top 1/3. That would give me full use of the second floor yet still have the smaller scale look of the Victoria that I like. I think that would solve most of the issues for me. I think? ;)
If It was me at this point I'd have paper, pencils, squares and my scale out and make a drawing to scale. As long as the rafter tie falls in the lower third of the triangle formed by the wall tops and the peak you're good.
Point to remember is that elevated rafter ties may require resizing the rafter (larger). Table R802.5.1 used for sizing rafters for different snow loads also has footnotes with the correction factors for different ratios. Further down there is a nailing schedule for the heel joint connection.
The photo showing the loft with the wood interior is using the truss roof structure not rafters and collar ties.
R802.10 Wood trusses.
R802.10.1 Truss design drawings. Truss design drawings, prepared in conformance to Section R802.10.1, shall be provided to the building official and approved prior to installation. Truss design drawings shall include, at a minimum, the information specified below. Truss design drawing shall be provided with the shipment of trusses delivered to the jobsite.
1. Slope or depth, span and spacing.
2. Location of all joints.
3. Required bearing widths.
4. Design loads as applicable.
4.1. Top chord live load (as determined from Section R301.6).
4.2. Top chord dead load. 4.3. Bottom chord live load. 4.4. Bottom chord dead load.
4.5. Concentrated loads and their points of application.
4.6. Controlling wind and earthquake loads.
5. Adjustments to lumber and joint connector design values for conditions of use.
6. Each reaction force and direction.
7. Joint connector type and description (e.g., size, thickness or gage) and the dimensioned location of each joint connector except where symmetrically located relative to the joint interface.
8. Lumber size, species and grade for each member.
9. Connection requirements for:
9.1. Truss to girder-truss.
9.2. Truss ply-to-ply.
9.3. Field splices.
10. Calculated deflection ratio and/or maximum description for live and total load.
11. Maximum axial compression forces in the truss members to enable the building designer to design the size, connections and anchorage of the permanent continuous lateral bracing. Forces shall be shown on the truss design drawing or on supplemental documents.
12. Required permanent truss member bracing location
I want to be clear to everyone on this board and anyone who buys my plans... I am not an engineer and my drawings (including the truss diagrams in the 1-1/2 story cottage plans) are not engineered or stamped - they are not going to provide the engineering information Don_P is quoting above. No stock plan will.
My non-engineered truss diagram, included in the plans, is for a sturdy site built truss using standard lumber, plywood gusset plates, construction adhesives and nails. It is there to provide guidance for folks who are in non-code areas or in locations where a truss truck can not make delivery. It has not been specifically engineered for your specific loads. That said, this truss has been built in lots of climates and is holding up very well. But, you will likely farm out this work to others as they can build and deliver a lighter, and more code friendly product to the top of your house. It might even be cheaper than building it yourself.
In most areas the owner or builder simply sends over the truss configuration diagram to the truss company (or to the lumber yard) and the truss company engineer, using a computer program, designs the truss, documents it to local code standards and puts specs and calculations on the truck for delivery to the site and the site inspector.
No owner builder is going to have to learn how to do all these calculations.
You can find old plans with site built trusses that were standard issue by Ag Extension offices to help builders and farmers build things before there were computer engineering programs and code required specifications. Many of these old buildings and trusses are still in service all over America.
Here is one example: http://bioengr.ag.utk.edu/extension/extpubs/PlanList97.htm#Roof%20Framing%20and%20Truss%20Plans
Can you point me to that truss configuration John?
It is not posted on the website Don, but is part of the plans. If you want to give me an email I can send you the diagram. john@countryplans.com