Construction Drawings
Our construction drawings were submitted to the city a few weeks ago, so we’re in a bit of a holding pattern while we wait for our building permits. This process usually takes around 10 business days, so we’re expecting we’ll receive them this week.
These latest set of drawings are quite comprehensive and illustrate in great detail how we’re planning on building the home. In particular, the cross sections really put things into perspective and give you a decent idea of how the house will look when things are completed (such as the 23′-9″ ceiling height when you enter the house.)
For the most part everything is the same as it was, however we have made a number of refinements since I posted the previous drawings. For instance:
- The length of the clearstory has been reduced significantly to stop it from encroaching into the living room. It now sits flush with the front bedroom, while the en-suite continues to extend about 4′ past it.
- We’ve reintroduced a step down into the living room. This means the ceiling height in the room below will be about a foot shorter, but Altius was insistent that we eliminate the bulkhead that would have resulted from the en-suite bathroom above. I think that’s a fair tradeoff, no?
- Each bedroom now has an updated window arrangement. The master has a larger set to better fill the space, while the others now have windows on adjacent walls for improved cross-ventilation.
- Because of grading restrictions we needed to decrease the pitch of our driveway, which unfortunately has caused a few adverse side effects:
- The garage now sits slightly lower, which means it will have a generous 10′ 4″ ceiling while the rooms below now stand at a paltry 6′ 11″. I can’t say I’m particularly happy about the lower ceilings, but our options are limited at this point. We’re planning on using INSUL-DECK for the slab floor in the garage (which isn’t illustrated in the latest drawings at the moment). Hopefully that’ll allow us to reclaim a few inches.
- We also needed to add an additional step into the house at the front door and in the garage door. Again, not exactly ideal but not the end of the world.
- It looks like we’re going to need a small retaining wall along the north side of our driveway. I assumed it would just be a small block wall, but Altius has illustrated it as a wall + planter instead. Much better, if I do say so myself.
At the moment, the drawings illustrate the use of ICFs for the foundation only, with stick framing and spray foam for the floors above. We really wanted to use ICFs to the roof, but it appears as if it’ll fall outside our budget. Sigh.
As usual, the updated drawings can be found in the documents section for your viewing pleasure.
Post Tags: altius, building permits, Design, drawings, ICF, windows
When ya gonna blow the old house up?
— posted on August 5, 2008Demolition is tentatively scheduled for August 11th… but we’re still waiting on our building permits. Soon. Very soon.
— posted on August 6, 2008I used to live at 330 Winnett Ave. in the early 90’s. I just read about your building project in the star and I came accross the story about your project. I love how thoughtful you are being. I have marked you in my favourites and will follow your project.
— posted on September 7, 2008Thanks Glen!
I must admit, this project has (at least for now) brought the neighbourhood together. I’ve heard such horror stories about neighbour protests and injunctions, and (knock on wood), we’ve had the complete opposite. It definitely reinforces why we decided to stay and build :)
— posted on September 7, 2008I see you’ve gone back to spray foam insulation and stick framing due to budget constraints. This is still a great choice, however, there are different ways of implementing it. Conventional insulation methods, where the cavity of between the studs and the outside and inside sheathing is insulated (whether by spray foam or otherwise) allows thermal bridging, which is basically heat transfer from the inside to the outside through the studs and other framing members. This severely reduces the theoretical R-value of the wall. You’re a fan of Mike Holmes (Holmes on Homes), as am I, and he estimates that approximately 25% of a home remains uninsulated due to thermal bridging through the studs.
The best way to avoid this (other than using ICF’s which do not allow thermal bridging) is to also insulate the home from the outside either using 1 to 2″ of rigid eps foam insulation boards with the seams filled and taped or spray foam insulation, in addition to insulation in the cavities between the studs. This will reduce the amount of insulation you need to spray on the inside the achieve the R-value you want. Insta-Insulation, often featured on Holmes’ show, is a big proponent of this exterior insulation method. In fact, Canada Mortgage & Housing Corporation, who publishes a wide variety of building construction related documents, recommends that houses be insulated on the exterior of the sheathing. Building Science Corporation (http:/www.buildingscience.com), a great organization that publishes a wealth of construction-related information, much of it free, has a lot information on their website about this. They produce a great book, ‘Builder’s Guide to Cold Climates’ (described as ‘A systems approach to designing and building homes that are safe, healthy, durable, comfortable, energy efficient and environmentally responsible’).
Given you have yet to frame the walls, you are still able to adjust the design to accomodate some external insulation to reduce or eliminate thermal bridging.
— posted on September 7, 2008I have to second Scott’s suggestion of additional insulation on the exterior to combat thermal bridging.
We built our own home (we were crazy enough to also do about 85% of the subcontract work ourselves, see http://newhome.daxack.ca) and would have loved to go ICF to the roof, but it was beyond our budget as well. As we were going with an acrylic stucco finish, the exterior foam was a given. However, with this finish, there needs to be rainscreen protection, which slightly ventilates the back of the foam and reduces its effective R-value slightly.
On the plus side, because of our ICF foundation, the stucco contractor needed to use 2″ foam instead of the usual 1.5″ so that it would be even with the ICF. In addition to this, the rainscreen protection came from placing the air barrier completely on the outside of the home. Many homes are built with the air and vapour barrier shared, with wrap around the end of floors to connect the barrier from one floor to the next. Having an entirely separate air barrier on the outside of the framing makes for a better air barrier, in my opinion (and in the opinion of our building inspector, who pointed out that insulation could be installed before the stucco was installed because it made the building air tight).
— posted on September 8, 2008I’ve inquired with our architects & contractor about the addition of exterior foam, however I’m a little concerned about the added width. I know this sounds somewhat trivial when you’re talking about 2″, but we’re a little tight through the middle of the house.
Regardless, it’s definitely something to consider and I like the idea of reducing the amount of sprayfoam we need as it’s quite expensive.
— posted on September 9, 2008By the way, I mean to type XPS (extruded polystyrene), which is closed cell, not EPS (expanded polystyrene), which is open cell.
As for cost, I am not sure that the cost will be any different, as you will have the additional cost and labour of installing the exterior styrofoam and foaming and/or taping the seams to offset the resulting thinner layer of sprayfoam insulation you will require on the inside, but the energy savings are worthwhile.
You could also preserve the racking resistance provided by the 1/2″ sheathing shown in your drawings by instead using metal strapping run diagonally across the stud bays, which many builders use. This would reduce your wall thickness by 1/2″.
Also it seems that even with the extra thickness of the exterior styrofoam, the total wall thickness would be very similar to the wall thickness you would have had when you were considering ICF’s for all floors, or am I mistaken? Sprayfoam on the exterior of a house, btw, is also a great alternative to to rigid styrofoam sheets as long as you properly accomodate for fastening the exterior cladding.
As for the sprayfoam on the interior, it is expensive but nothing beats it for completely air sealing and completely insulating the house. This is especially true when you consider that the R-value of a wall is reduced by double-digit percentages due to even the smallest holes dues to improper sealing of the vapour barrier to protrusions in the wall and/or improper installation of conventional (batt) insulation. Actually even if you are really determined (as few installers are) it’s almost impossible to do a good job with protrusions in the wall created by s pipes, cables and electrical boxes using tuck tape, acoustical sealant and poly. This is not the case with sprayfoam insulation.
— posted on September 9, 2008Hi Jeremy,
Just found your site and now I can’t stop reading it. Great
info.
A question: On a previous post you had said that the cost for
— posted on September 26, 2008ICF up to the roof would have been about the same as stick
frame but now you’ve changed your mind. What happened? What
was the difference in cost?