Ask The Wizard

This category of our Blog is filled with questions submitted by you, our customer, and answered by our in house expert, aka "The Wizard". Feel free to browse through to see if your question has already been asked, and answered. If it hasn't, you can submit your question for our expert on the "Ask The Wizard Page" under the Blog tab at the top of the page.

What is the difference in cost of using PinkWood vs. not using it?

Q: What is the difference in cost of using PinkWood vs. not using it per linear foot?

A: We offer many PinkWood products but I am assuming that you would be talking about our I-Joists. The PinkWood I-Joists vary in price according to the depth of joist used but generally, it’s about 20% more than untreated I-Joists would be.  Though the cost is significant, the added benefits of a fire-retardant, mould and moisture resistant engineered product may be an important consideration when deciding what building materials to use.

How does the building inspector conduct a framing inspection on your Pacific SmartWallsTM?

FOLLOW UP QUESTION FROM A PREVIOUS ‘ASK THE WIZARD’ – Click here for details.

Q: How does the building inspector conduct a framing inspection, as the 2×4 studs supporting the building are covered up with plywood on one side and foam insulation on the other side? Are the studs solid wood or finger jointed material? Can the studs that are ganged together where the panel edges meet be nailed to each other and the floor, or are they just supported by the second top plate? These panels kind of look like SIP’s, except they don’t have the wallboard on the interior side. Who inspects the framing, sheathing and wall assembly?

A: Here are a few photos of our Pacific SmartWallsTM being assembled at various stages in our factory. (See photo gallery below.) These will help visualize the components that make up our panels and how they are put together.

The critical studs are easily visible but you are correct, the intermediate studs are not because they are hidden behind sheathing on the exterior and behind polystyrene on the interior. The intermediate studs are spaced at 16” o/c or less and are always located at the vertical seam between polystyrene panels. Because the polystyrene is dadoed (wrapped) around the stud, it is only 1/2″ thick at the seam locations and if there is any doubt as to their location, the 2×4 studs can easily be detected by poking the point of a nail in and confirming solid wood behind. From the exterior, the sheathing is nailed per BCBC Part 9, Section 9.23.17 and the nail heads show where the studs are. Once this information is known, the inspector can conduct a framing inspection on the remaining panels.

To answer your question as to whether the studs are solid wood or finger jointed material. We always use sawn lumber (minimum grade No.2 SPF or better) for all studs and headers.

Where the panel edges meet, we design our panels to be nailed together with 1 row of 3-1/4” nails @ 8” o/c each face, staggered. The depth of the factory installed polystyrene allows a 1-1/2” wide nailing surface of the 2×6 end stud to be exposed. Nails can easily be driven from each side of both panels, resulting in a 4” o/c nail spacing. On the exterior, the sheathing is held back 3/4″ on one panel and extended 3/4” on the adjoining panel to allow it to be lapped at the centre of an end stud. This overlap of sheathing is then nailed to the next panel with 3” nails @ 4” o/c. At the tops and bottoms of the panels, sheathing is lapped in a similar manner and nailed to top and bottom plates with the edge nailing pattern being 3” nails @ 4” o/c and the in field nailing pattern being 3” nails @ 6” o/c.

Who inspects the framing, sheathing and wall assembly? We do. We have a very strict quality control program in place that is adhered to with the assembly of every panel. Assembly tolerances and material quality are checked regularly and any component not meeting our standards is rejected.

Best Regards,

The Wizard

As the wall panels are pre-assembled in your factory, is structural engineering required?

Q: As the wall panels are pre-assembled in your factory, is structural engineering required?

A: Unless there are other elements in the building that require a structural engineer’s attention, using our wall panels in a Part 9 (Residential) building does not. The Pacific SmartWallTM panel is often mistaken as being a Structural Insulated Panel or “SIP”. Structural Insulated Panels (SIPs), are an “Alternative Solution” as defined in section 2.3.1 of the Building Code – Pacific SmartWallTM panels are not. Our Pacific SmartWallTM panels are built in our factory to conform in all respects to Part 9 of the Building Code and no claims for enhanced performance over and above those allowed in the Building Code are made. The materials used are conventional in every way with the insulation being rigid instead of batt type meaning our Pacific SmartWallTM have a higher R-value. The wall panels are easily inspected as nothing is hidden from sight and where loads must be transferred from above to below, full width multi-ply studs are used.

Other than being built to very tight tolerances and assembled in a clean, dry factory, there is no “magic” in our panels and as such, structural engineering is not required.

I hope this answers your question and if you have any more concerns or questions, please feel free to contact me any time.

Is it possible to have a vaulted ceiling for a little over half the house and then have a loft on the remaining space?

Q: I have just purchased my first home in Port Renfrew. It is a 15 year old home but the roof is in very poor condition. The dimensions of the house are 25×40 it is a single story rancher style house with an 8 foot ceiling. We were planning on replacing the trusses to gain a vaulted ceiling. My question is this, is it possible to have a vaulted ceiling for a little over half the house and then have a loft on the remaining space? Would I have to build rafters or do you design a truss for a loft?

A: If you’re going to be replacing the trusses on your roof, then your options are unlimited!  Yes, you can have part of the roof in vaulted trusses and the rest in a loft or “attic truss”.  This all depends on the roof slope that you would be able to use and is limited by your location and ground snow load.  I would assume that the span of the trusses would be running in the 25 foot dimension and depending on the style of roof you want – gable or hip – you could end up with a very nice vaulted truss that would give you an impressive ceiling.

As for the loft area, I would recommend an attic truss, which is a truss that not only provides a roof profile, but also has a “built-in” floor area for living space.  Now, with that said, if your span is running in the 25 foot direction and you would be willing to use a fairly steep slope – say 10/12 or more – then you could expect to get a “live-able” space of around 14’ wide and 8’ tall in the centre. There would be knee walls that would start at the outside edge of the loft area and slope up to the 8’ ceiling on each side.

Check with your local building inspection department to see if this is an option as you may have a height restriction, in which case you may be limited on what you can do.

If you would like to pursue this further, please contact one of our sales representatives at the numbers listed on the website and they will be happy to help you design a roof that fits your budget, meets your expectations and satisfies the building inspector too!  They will provide you with a written quotation and show you all of your options.

I hope this answers your question and if you have any further questions or concerns, please feel free to contact me again and I will do my best to answer them.

Thanks again,

The Wizard

What kind of trusses would I use?

Pacific Plan: Caribou

Q: Let’s say I was building the Caribou home (25’x48′), what trusses would I use considering the pitch is 12/12 I believe. There is not a lot of snow where I live.

A: The trusses for this plan would consist of parallel chord trusses for both sides, being supported by a large flat girder that runs the length of the building. A parallel chord truss allows for maximum insulation while cost effectively providing the required span.

Thanks,

The Wizard, (aka Larry Schwazer)

What do the numbers on my truss layout mean?

Q: What does the number 10-19-12 mean on a truss drawing?

A: Truss drawings and layouts vary from one manufacturer to another but the general information is usually the same. There are a minimum number of elements that must be displayed on every drawing and this information can be placed anywhere on the drawing by the design software supplier.

The numbers that you referred to have me a little bit puzzled because they don’t follow either of the two formats. The first format is “builders units” which break a dimension down into feet, inches and sixteenths as this is the degree of accuracy your trusses are manufactured to. The number format is FF-II-SS (where FF stands for feet, II stands for inches, and SS stands for sixteenths). For instance, a number like “10-06-08” would be 10 feet, 6 inches and 8 sixteenths (or ½ inch if you prefer.)

Another formatted number on truss drawings is the designed date and it can take on several formats. The most common is MM-DD-YY. For instance the run date might be 6-30-12 where the month would be June, the day would be 30 and the year would be 2012.

The numbers that you wrote in your email do not follow either of the formats because if it were builders units, we would have 10 feet, 19 inches and 12 sixteenths (or ¾” if you prefer). The output would never show more than 12 inches or 15 sixteenths. The remainder would be added to the next unit so that the number would become 11 feet, 7 inches and 12 sixteenths. If it was a date, it would read October, 19, 2012 which, we know, has not yet arrived.

I hope this helps to understand your truss drawings a little better and as always, don’t hesitate to contact us should you require further clarification.

Best regards,

The Wizard, (aka Larry Schwazer)

Can I modify 5 or 6 trusses to lift the ceiling height in my barn?

Q: I have a question on how to proceed on my pole barn I built. When I built the barn, I built it with 9’6″ ceilings thinking this would be enough height for me. Well I recently bought a large boat and want to store it in the barn. Problem is I need about 12′ of ceiling height. The trusses now are 5/12 and are 5′ o/c. All I need to do is modify 5 or 6 trusses on one end of the building. I was going to open the gable end of the building to put in a sliding door. Question being, can I modify 5 or 6 of the trusses to lift the ceiling height by about 2.5′ or should I try to buy 40′ scissor trusses? The building is all metal with very little load weight? Thank you so much!

A: Well, I hate to say it but the 40’ trusses are probably designed to their maximum strength already and any modifications done would not be easy or cost effective. Once you start getting over 35’ in clear span, there just isn’t really a way to modify/butcher a truss and have it still perform as intended. Once you remove a section of truss (in your case most of the bottom chord), it must be replaced with some form of lumber – either engineered or conventional. The problem is that conventional lumber is usually only available in lengths up to 20’ and when placed at an angle to form the vaulted ceiling, it would be too short and offer very little structurally.

Engineered lumber is both expensive and awkward to work with in long lengths, not to mention in an enclosed building. And I’m not convinced that a simple solution could be found without a fairly expensive trip to an engineer’s office!

In summary, you are probably going to be much better off and have a lot less trouble if you can buy some custom built scissor trusses designed to your exact specifications.  It will be both less expensive and it will look a lot better too. You will be happier that way. 

Larry Schwazer  (aka “The Wizard”)

Could I modify my trusses to gain ceiling height?

 Q: My garage is 30′ x 36’ with a 6/12 pitch roof. I would like to know if I could modify the truss bottom cord to gain ceiling height inside the garage; my trusses measure 30′ and are on 4′ centers with a steel roof.

 A: Thanks so much for contacting me through our website. It sounds like you built a garage that started out big enough, but now you need more room! It seems that happens quite often.

 Depending on where your building is located and what your ground snow load is, the amount of modification that can be done to your trusses will be limited.  The biggest gain in ceiling height would be to vault the bottom chord at 3/12 slope. This would give you a height in the middle of about 43 inches.  The downside to all of this is that you have to basically render your entire truss system useless and make up the structural short comings with 2 lengths of LVL beams, crossed at the middle to form the new ceiling. LVL beams are both very heavy and expensive and the final design would need to be drawn up by an engineer. The bottom chord and most of the webs would then be cut at the new slope and the LVL beams would provide the structural stability.

 In reality, this is a very expensive and time consuming way to gain some height in your ceiling, not to mention the engineering time required to come up with a specific solution that would work for you.

 You mentioned that your trusses are 4′ on centre. For 36′ that would mean that you have a total of 10 trusses. I wonder if it would be possible to raise your roof by removing the trusses and building pony walls on top of your existing walls. You could then set the trusses back on top of the new pony walls and you would have achieved some extra height. I know that you would need more siding and it would change the look of your building slightly but in the end, it is something that you can do yourself and not have to involve and engineer. It may very well work out to be cheaper too.

 Of course, there is always the option of replacing the entire set of trusses with new scissor trusses.

 I hope this gives you a little help so that you can make an informed decision should you decide to pursue this further.

 Take care and thanks again for contacting me!

 Larry Schwazer, (aka – The Wizard)

Is it possible to use LVL as a joist?

Q: Is it possible to use LVL (orange painted wood 1 3/4″ thick) as a joist? Is there a table chart for that?

A: Thanks for contacting me through our website with your question about using LVL as a joist. The answer is YES! But please keep in mind that although you may be able to span a greater distance, there will be some drawbacks when it comes to making holes for services to run through. I-Joists are better suited to this and allow substantial sized openings to be made in them for running ducting, electrical and plumbing. LVL’s are quite restricted in the amount of holes that can be placed in them. I-Joists have a minimum flange thickness of 2 1/2″ where the LVL is only 1-3/4″. This does not present a problem as the LVL joists readily accept flooring screws and tend to hold quite well.

Another consideration is that the per foot weight of an LVL floor will be somewhat greater than that of an I-Joist. They may be a little more difficult to handle on the job site.

There really are only span tables available for I-Joists and an LVL joist would require us to engineer it for a specific application.

If you have a set of plans and a floor layout, we would be more than happy to provide you with a free quotation using LVL joists.

Thanks again for your question,

Larry Schwazer (aka The Wizard)

What would the pitch of a vaulted truss ceiling be if the roof pitch was 12/12?

Q: I was wondering if you could tell me what the pitch of a vaulted truss ceiling would be if the roof pitch was 12/12 and say a 16′ span.

A: Thank you for contacting me regarding your vaulted truss question. The fact is, you can have any pitch you want up to and including 12/12 depending on the snow load and the overall height at the exterior walls. A conventional scissor truss could go as high as 8/12 pitch with a standard heel height and we could also do a parallel chord truss at 12/12 inside but this would mean that you would have a higher heel at the wall.

Please feel free to contact me again if this doesn’t answer your question.

Larry Schwazer, aka “The Wizard”