Party wall progress

With the framers off for the weekend break, the ICF install company decided to stack the styrofoam blocks while the main floor was empty of other trades.  Ryan, while working by himself was able to install 10 ft of block and the bracing on the side of the floor that has been sheeted.  On monday, the framers will install the remaining floor material and the ICF can be prepped for the pour.

With ten foot ceilings on the main floor, the ICF wall appears massive from the street, particularly as it is the first material to be installed above the main floor level

First floor framing begins next week

The framers suffered some additional poor weather that resulted in shortened work days due to the blizzard and wet conditions.  This hasn't prevented our insulated concrete form crew from arriving to unload their material onto the first floor and prepare to begin the main floor party wall assembly.

Our surveyor returned to site and took an elevation reading of the main floor wood subfloor.  This has been submitted to the City for review.  The City will soon issue us permission to continue framing the  'above grade' elements of the building.

Here is a quick photo of the main floor that has been loaded with ICF blocks and scaffold material

Below is an image of the material used to connect the lumber framing of the building to the concrete middle wall.  The heavy gauge screws involved (8 per hanger) have proven to be a problem with a few getting bent or stripped.  Replacement screws for these proprietary screws have been almost impossible to locate.  Fortunately there is a distributor in Calgary that has provided us with an extra 25.

framing progress

With the foundation complete the framers have begun to install the main level floor joist system.  Once sheeted with subfloor, the surveyor returns to the site to shoot the main floor elevation to ensure the height of the house is within the development permit parameters.  Going over height can be a serious breach of the planning permission and is an extremely undesirable outcome.  By measuring the height of the main floor it is possible to double check the final height of the highest roof peak.

With the city inspection and approval of the foundation now complete, it is now possible to schedule the backfill of the foundation.  Due to the walkout rear basement and below grade patio that was excavated to four feet below grade, the backfilling technique used will diverge slightly from typical calgary practice.  Essentially the area of the slab that was dug up and the sunken patio fill must be compacted as it is filled with loose soil.  Since a machine with a compactor attachment is available, compacting of the entire perimeter foundation is possible as an added bonus.  This should result less future settlement, and closer tolerances for our grading efforts.  Typical calgary construction practice is to backfill without compaction.  Due to the soil type, loose fill placement, and freeze thaw or moisture based natural compaction each year, significant uncontrolled settlement often occurs if backfill is not properly compacted.  By compacting the entire excavated area, far less settlement should be observed.

The first floor joists have been installed on the left side house

the middle wall

Since most home buyers don't like to hear their neighbour, or be subject to having the neighbour start a fire that is able to jump across the party wall and burn their house down, the insulated concrete form   (ICF) party wall has become a popular, if costly option.  The ICF is exceptional insulator for sound and when covered by drywall is highly resistant to the spread of flames.  Our ICF contractor (Harold) has utilized a particular brand of ICF called the 'fox block' many times for this application, and has poured party walls as high as 13 ft, a very impressive figure considering the weight of the wet concrete that the lightweight forms must contain without rupturing .  Fox block is an Alberta made product, one of many innovative high tech or manufactured materials that are available for those that can stretch the budget to attempt to build a better home.   Integer homes incorporates ICF party wall as a standard component of the project in houses priced above a certain threshold.  Wood party walls, while code complaint, are far inferior at blocking sound transmission between two houses.

Harold figured out how to manage our earlier issue with the stepped footing.  The ICF block was scribed to fit in the stepped footing area, which allowed us to proceed with pouring the middle wall without having to have compacted and backfilled the area under the excavated slab portion of the walkout.

The ICF block is scribed to fit in the cavity left when the under slab area was excavated.  Once the native  soil material is removed it can not be filled back in and be expected to safely bear the weight of a concrete wall.  In this example we removed soil to form the back wall of the house, so to use fill to bear the weight of the ICF would not be advisable.  Instead our contractor has used the ICF bricks themselves as the footing for the party wall above.

In a future post a description of the engineer's selection of the technique used to fasten the floor joists to the styrofoam block and into the concrete will be discussed in greater detail.  The octagonal steel boxes visible that are embedded in the styrofoam are part of a two step process that allows the laminated veneer lumber (LVL) ledger board to connect to the ICF via a simpson strong tie hanger without having to core into the concrete ICF block, because the attachment surface (the octagon) is already connected into the concrete before the pour.

This is the middle wall that divides the two houses.  The ICF structure will continue to the top of the ceiling of the second floor where it will support the roof trusses.  

Waterproofing and weeping tile

Without the waterproofing and weeping tile installation, permission to backfill cannot be received.  AG Construction is a Calgary contractor that does a good job of foundation coat and weeping tile.  As an added bonus they have tremendous experience aiming and firing the gravel slinger to cover the weeping tile at the base of the footing.  Unfortunately at this job site, due to a tree being in the way, and other site access problems, they decided the job could not done until the floor is installed on the foundation. However, the lack of power on site meant the floor was delayed, and it would be better structurally for the new concrete walls to have the floor installed prior to adding the weight of backfill to the foundation.  No weeping tile means no backfill however, thus a typical construction stalemate ensues.  At this point, as the builder, you must step in and make something happen to overcome the hurdle.  Ordering the weeping tile guy and gravel slinger to arrive and offer to take on all liability should something go awry is one option, and in this instance proves successful.  Once the process is complete, the city can be called to book the pre-backfill inspection.

foundation coat has been applied and the weeping tile is wrapped around the footing

the slinger in action.  they will shoot a few tonnes of gravel in the foundation to assist the plumber to bed his pipes under the slab

the slinger is a tremendous way to move gravel, far easier than the wheelbarrow technique

the weeping tile must be completely covered in gravel.  if you do not do so, expect to fail the pre-backfill inspection

Temporary power

Gaining temporary power is an absolute must at this point in the process.  The local utility provider actually hooks up the power, but this only follows a successful series of steps that lead to the lineman connecting the new meter.  Here is the process laid out in a simple and easy to follow series of steps.  However, confusion and aggravation is often a guaranteed element of successfully having the power hooked up.  Get ready to suffer defeat at any of these steps and face considerable delay in having the power connected.

At least six code violations here, maybe more if the inspector looks closer

Dave the electrician has visited the site.  He is extremely good at his job and promises zero deficiencies

The all important green sticker has arrived, meaning Dave's efforts were a success

HERE IS A SCHEMATIC OF THE TECHNIQUE USED TO GET TEMPORARY POWER

1. buy a 12 ft 6x6 treated lumber post - then figure out how to transport this to the site (secret - ask the cribber to do you a favour and deliver it as he has a truck large enough to safely transport this long post).  
2. have the excavator did a four ft deep hole and plant the post for you so that about eight feet of post remains above grade, if you can even locate grade at this point thanks to the excavation and dirt pile everywhere.
3. get your temporary electrical panel from wherever you stored it, and hope it fits in your truck.  In this case the panel was already suffering from significant damage due to being tipped over at the last job site by a careless bobcat operator, and the mast was damaged.  This will inevitably cause problems later.
4. get on the proper web page with the utility company and request the site id.  You are going to need to know some technical stuff, like number of wires, amps, volts, permit number (secret - only the electrician can get a permit number, so if he hasn't done so, you are really stuck at this step and cannot proceed).
5. ensure you have a retailer and an account set up for the new property.  If you don't be prepared to pay a substantial security deposit.  Fortunately the last account from integer homes remains in good standing with enmax so this is fairly straightforward.
6. hang the panel and get the electrician to visit the site, ground the panel and make sure it is in good enough condition to pass inspection (secret - your electrician must come to the site to make adjustments and if he doesn't it almost guarantees a failure).
7. have the electrician call for inspection.
8. arrive at site the following day to look for the green sticker from the building inspector (secret - get the electrician to actually visit the site and repair the half dozen deficiencies on your damaged panel).  Since there is no green sticker, call the electrician and ask him to dispatch someone to fix the panel and recall the inspection.
9. the next day, arrive at the site and locate the green sticker - finally you have passed.
10. call enmax and request the meter connection at the temporary pole.  They will need every type of information available, such as site ID, address and postal code, account holders confidential information.  Enmax will then indicate two to five business days are needed to hook up the panel.  This is where events can go seriously wrong.  Expect major grief at this point in the process if the application doesn't pass Enmax' internal requirement.
11. two days later tour the site - no power.  Three days later tour the site - still no power.
12. the next day tour the site - it is now friday at noon.  there is no power and this is very suspect.
13. call enmax to inquire about the scheduled requirement for the connection.  At this point you must hope you are calling the correct department (secret - inevitably you are going to be standing in a muddy back yard or sitting in a car while on your cell phone.  Pre-program your cell phone with all possible enmax phone numbers and ensure the name on the number is the appropriate department.  Wait on hold a considerable amount of time for the operator.
14. promise your framing crew that power delivery is imminent (secret - don't do this until you have a strong inclination that power actually is imminent).
15. after waiting on hold an indeterminate length of time, enmax will answer the call after suggesting you fax them a request. If you have a fax machine in your vehicle, use this now.  If not, hold the line.
16. Now you have the enmax employee on the line, request an update.  After some awkward silence you will be told that your application for power was not recorded, or based on some technicality not successful.  Here is where you have a choice, you can wait another two to five business days, or begin to have a freak out.  Remember, you have promised your next crew that power is available on site and they are planning to start work and have scheduled your job and that means they have completed other work or have avoided taking on new work to do your job.  No power means they will not be showing up tomorrow.
17. After the successful freak out enmax becomes more compliant. They offer to call you back with a solution.
18. Someone from enmax emails you a bizarre and incomprehensible reason power is not on site.  The reason is not credible since their own system generated the address, site ID, and have taken every possible piece of information related to billing and ownership of the site.
19. Call your crew and give them the bad news, offer to rent a large generator the next morning
20. Enmax calls your cell phone and offers to fast track the connection, but not until Monday.  They note that it is still within five business days so technically that is within their accepted service standard to do so by Monday.
21. Fill out the form enmax has sent you requesting feedback on its service and call centre staff - make some extremely nasty vitriolic comments and wonder who is going to read the survey results and what they might think after they review the colourful language and phrases
22. Wait for the power, get generator to site.
23. Enmax arrives to connect power shortly after generator is delivered.

Cribbing

Our cribbing crew (Billy's Basements) is very efficient, they can pour multiple basements each week, all year round (weather permitting).  They use the conventional 9 ft forms and actually have a variety of crews to do the footing, crib the walls, place the concrete and eventually tear off the forms.  In addition to Billy's crew, we are using a more specialized crew to install the middle wall of the basement, and both upper levels as well. They stack the insulated concrete forms better known as ICF, use a different rebar pattern, and place the concrete.  Because the ICF needs a very flat surface, they had to get creative to account for the stepped middle footing needed to dig deep enough to go below the frost layer in our walkout.

Another issue is the weather.  February proved to be exceptionally cold and many days pouring of concrete, even the heated variety, is impossible.  Typical of Calgary construction, weather makes everything more difficult and costly.  Eventually a window of good weather opens, and the pour takes place well above the freezing mark.  Within two days the forms are stripped and we can proceed with the remaining pre-backfill construction requirements.

The inner forms are up and the outer forms will quickly follow

Walls have been poured and stripped

Footings

With a break in the weather and the excavation complete, the cribbing crew is able to form the footing.  At this stage a soil bearing report and soil test are required to determine the sulphate content of the soil and its capacity to bear the tremendous weight of the house we are going to be applying to the footing.  In addition to these tests, the structural engineering firm has also provided a detail for the  various footing types we are using, this largely relates to a rebar plan and width/height of footing.  Note our middle footing is actually the deepest and widest footing.  It will be bearing a tremendous weight from above, this will be described in detail in an upcoming post.

the middle footing has a different rebar detail and contains significantly more concrete

At the rear, the footing is stepped to account for slope of the lot and the walkout rear basement access that is planned.  This creates some added complexity for the middle wall, it must be one level in order to suit the specific requirements of the material we are using for the sound/fire barrier between the two houses

here is a copy of the engineered plans for the footing and basement walls

excavation

Digging of the basement is a loud and dirty process, and with uncooperative weather an additional week delay is inevitable.  The hydraulics that operate the bucket on the excavator suffer costly wear and tear while moving earth and ripping our frozen soil at temperatures below minus 20 celcius.  On cold winter mornings, the machine sits and waits for better weather.  Here is a picture from early on in the process, (February 11 2014)

frost conditions don't help with efficient excavation of the basement however warmer weather is in the forecast

demolition

In order to clear the property for the duplex construction, we must remove the existing house on the site.  We purchased the house from Richard G, whom we met after an introduction from Steve B in early 2012.  The house was a typical 60's era bungalow, and in livable, but fair condition compared to others of its kind.  As is the fate of most homes of this type, the only economic solution to removal of the house is demolition and disposal of the demolished house is the landfill.  While other options exist for more valuable homes, such as relocation, this one was far from salvageable.  Off to the dump it went, and in only about two days.  Some valuable materials are salvaged from the house, mainly copper pipe used in the main plumbing stack.  Unfortunately demolition attracts unwanted scavengers who trespass on the site and steal whatever valuables can be located.  An observant neighbour identified a trespassing scavenger and called police, leading to an arrest.  Thanks neighbour (definitely not worth getting arrested over a few pounds of scrap copper, my greater concern is liability for someone falling in the hole and getting injured).

Here is an image of the house just prior to demolition

Jason is a highly skilled operator of the track hoe and takes little time to remove the debris