Construction Archives - Page 2 of 2

foundation – piers

At about a week forms for the grade beams were stripped and the excavator came to fill around and over them. We ended up putting down about 40 tons of stone over the grade beams to provide a base for a cement slab for the garage/storage area.

The plans called for 19 12″x12″ concrete piers to support the main floor of the home. The concrete crew tied reinforcement to the dowels coming up from the grade beams, erected forms, and then we poured concrete again.

Drawings showed 4 each 16″ long 3/4″ bolts at the top of each pier, at the corners of a square with 5″ sides. It was not clear to me how they were going to place these bolts, seemed like the plan was to just stick them in by hand after the concrete had been poured to the required elevation. That did not need like a great plan to me, so I did some poking around and found some adjustable anchor bolt jigs called AJ Speedsets. Concrete crew probably thought I was nuts, but I ordered these jigs and got the bolts (and nuts and washers) from Portland Bolt. I assembled the jigs and the crew tied them in to the pier reinforcement. Unfortunately they did not really keep an eye on centering as they poured the piers, but turned out that alignment of the bolts between piers was not super critical. Nuts were threaded on to the bolts and used to adjust 1/2″x11″x11″ steel plates on which the steel beams would rest (with an additional bearing plate that fit between the bolts). Then the space below the plates was filled with non-shrink grout. So after everything was together the bolts were no longer supporting anything, the steel beams were on plates that were on grout that was on the top of concrete piers.

AJ Speedset ready for installation, bolts 5″ apart, roughly 7″ bolt circle

Bolt assemblies embedded in tops of piers (made some plastic/tape covers to slow down corrosion)

Typical bearing plate with nuts below to adjust, W10x22 beam welded to plate

Forms at pier tops for non-shrink grout to fill space below steel plates

Grouted pier top, W10x30 on bearing plates

I am sure they are strong, but the piers came out a little rough. The sub offered to let me pay for rental and deposit of new forms, in hindsight perhaps should have done that. At some point will clean the piers up a bit, maybe grind them a bit and/or apply some stucco.

foundation – grade beams

Once the piles were in the excavator came out to dig trenches for the foundation’s grade beams, which were drawn as 2’6″ wide by 2′ high, with the bottom of the beams at an elevation of 3′, which was 4’8″ below finished grade. The structural engineer indicated that the bottom of the grade beams should be at least 3’6″ below grade to avoid any frost problems.

Excavation around piles and trenching for grade beams completed

Next the concrete subcontractor’s team assembled the forms for the grade beams and cut the piles off such that the pile tops would be embedded into the grade beams by 6″. I had asked the pile driving contractor about treatment of piles where cut but they either did not know what to do, or didn’t want to have to do anything. The plans called for cut end treatment per AWPA M4-84, I figured out that meant a product called tenino copper naphthenate 2%, so I ordered a gallon of that from poles.com and treated the cut ends of the piles myself. No cap was required, the grade beams just get poured on top of/around the pile tops.

Forms for grade beams in process, some of the piles cut

I had gone back and forth with the structural engineer on #6 (3/4″) vs #5 (5/8″) rebar for the grade beams, the concrete sub said that #6 was unusual for residential construction, but if we dropped from 6 to 5 the engineer wanted to add bars. So we decided to use the #6, but have the rebar supplier, Harris Rebar, pre-cut and pre-bend for us, including a bunch of #3 stirrups. The structural engineer also called for galvanized, after discussing we backed off on that and went with plain black bar, as this stuff was going to be encased in concrete and below grade, as well as probably over engineered. The engineer also wanted placement/shop drawings for the rebar, when I figure out what that meant I did the drawings myself.

Grade beam stirrup placement sketch, on 18″ spacing, with 3 at 6″ spacing either side of pier locations

Grade beam rebar placement diagram, laps at >= 80 bar diameters

Dowells for concrete piers tied in to grade beams

We were in to December now, which is not an ideal time to pour concrete. The structural plans called for 5000 psi cement, I managed to get that dialed back to 3500 psi to save a little money, and I think we ended up using 4000 psi. When we were ready to pour daytime temps were in the 40s and overnight temps in 20s and one night in the teens. So O&G used hot water, a non-chloride accelerator, and a mid range plasticizer. It took 7 truckloads of cement, I think about 63 cubic yards.

Getting ready to pour concrete, pump truck and snout

Two pours in the neighborhood on the same day!

Grade beam pour complete, 7 truckloads of concrete

I pushed the cement sub to put blankets on the grade beams for some thermal protection, and also pushed back against pulling the forms off too quickly.

For this first pour I had a lab come out to catch and test samples of the concrete. Two cylinders tested at 3980 and 4120 psi at 7 days, and six cylinders from two samplings averaged about 4500 and 4900 psi at 28 days. So despite the cold the concrete strength was good.

foundation – pile driving

Based on two test borings our Geotechnical Engineering Report concluded that piles, either timber or helical, were required to support the home. This seemed consistent with foundations for a few recently completed homes in the neighborhood, one was on timber piles, and a couple were on helical piles with grade beams. Our test borings reached refusal at 39 and 41.5 feet below the surface.

Our structural engineer thought that timber piles were superior from both engineering and cost points of view. The downside was concern about damage to an adjacent home from pile driving vibrations. Helicals were not a lot more expensive, but the chance of overages with them was probably greater, they would have to go down about 22′, and at that depth there would be multiple sections with joints, so if you fetched up against a rock or something before you got to depth you cut the pile off and try again in a different spot, and the different spot means you are redesigning your grade beams. So we decided to give the timber piles a go. I suppose we could have run them right up to the main deck, but our foundation design called for grade beams and concrete piers, a much cleaner looking approach, and better suited to the prefabricated construction approach as the precision of concrete piers coming off grade beams would be higher than timber piles sticking out of the ground (and probably requiring a bunch of bracing).

First step was to get the surveyor to come out and mark the pile locations. He used giant nails with pile numbers written on a piece of plastic. I was not sure whether excavation for grade beams would be before or after piles were in, answer was after, so a bit more work for the excavator to dig around the piles.

Our lot only has one home on an adjacent lot, the other side is a small park. The owner of the adjacent home was quite concerned about damage from the installation of the piles, so in addition to engaging a geotechnical engineer to monitor and log the pile driving operation we had them do a survey of the adjacent home to document the condition before the pile driving operation, and during the pile driving they monitored vibration along the lot line. A couple of piles were 15-20′ from the adjacent home. Thankfully the soil conditions contributing to the need for a deep foundation system were also conditions that were not conducive to transmission of vibrations, which remained below acceptable levels even for the piles closest to the adjacent home, and way below acceptable levels for the piles that were further away.

The timber piles were 45 foot long CCA treated Class B southern pine with 8-inch tip and 12-inch butt minimum diameters.

The piles were installed with a Vulcan #2 single-acting air impact hammer with a McDermid base. The ram was 3,000 lbs and dropped 2.4 feet. Required pile working load was 25 tons, based on that they figured out that piles needed to be driven until it took at least 8 blows per inch. As the movement of the pile slowed down they marked 1 inch intervals on it and someone stood there watching the marks and counting blows. I don’t totally follow, but they did some sort of wave equation analysis to confirm we were getting a working load capacity of at least 25 tons.

The hammer and rails for same were suspended by a crane, and the crew jockeyed the thing around to get it vertical and then started driving. I forget the size of the air compressor that they used, but it was a big one.

First pile going in!

Piles were installed to depths of 18 to 41 feet below the existing ground level. There was an intermediate layer that most of the piles pounded through (I think the crew was always hoping they would fetch up in that layer, would have been quicker that way). Occasionally they would also hit a soft spot and the pile would drop several feet with a single blow. Piles were cut off just above ground level and then we did an as-built survey, which showed that all piles were within inches of where they were supposed to be (plans indicated a tolerance of 3″, which I think we were within). We were very happy about that because it meant we did not need to make any adjustments to the plans for the foundation.

construction drawings

As we were securing our initial (Coastal Area Management, or “CAM”) approvals Turkel was preparing a purchase order that would take us through the detailed design process and the procurement and assembly of a prefabricated “package,” leaving us with a watertight shell, including windows and exterior doors, which we would then finish with a local builder (walls left open for installation of MEP systems, insulation, etc.).

The purchase order included:

Construction and permitting drawings
Permitting support
Shop drawings
Procurement and assembly of the package
- Trusses and framing, architectural glulams, etc.
- 2×6 on 16″ exterior walls
- Huber ZIP sheathing (1/2″ exterior walls, 5/8″ roofs)
- Warmboard-S subfloors
- Marvin Contemporary windows (DP50) and a Marvin Multi-Slide door (DP40)
Local builder identification/vetting/selection

The purchase order did not include:

Foundation (<=0.25″ out of square, elevations within 0.25″)
Structural engineering
MEP
Roofing, cladding, flooring, interior doors
Shear walls/moment frames (per structural engineering)

We had two main concerns with the purchase order, neither of which were show stoppers, but were still concerns:

There was no transparency into costs, for example we had no idea what the window package cost was, or what the markup on same was.
Somewhat related to that, this was a fairly large turnkey project with conveyance to us at completion, so we were being asked to assume a level of credit risk that is unusual in new home construction (where you would normally have a number of payments, with lien releases along the way, so you would never have too much exposure to your builder or a subcontractor). If we had been funding this portion of the project with any debt and the lender was paying attention this probably would have been a problem.

A prior Turkel client we spoke with had contracted directly with the window provider and also with the provider of the building components, which would have addressed both these concerns, but Turkel pushed back hard on this approach. The lack of transparency into costs was particularly frustrating as we started working through the details of the window package, more on that in a bit.

So with the CAM approval behind us the goal now was to get a building permit ASAP, and to get on with the construction. Prior to the CAM approval we had worked through some different options for structural engineering and ended up engaging The DiSalvo Engineering Company directly (rather than through Turkel, which would have added a 20% markup). The DiSalvo contract included the preparation of stamped detailed plans for the foundation and structure of the home and periodic site visits to check conformance to plans.

So on to the process of getting to building department approval of construction drawings:

5/14 – Turkel provided a DD (design development) set of plans to get the structural engineer going and to help with initial efforts to identify and select a local builder.

The DD set was provided to DeSalvo 5/19 and there was back and forth between them and Turkel. DiSalvo provided schematic framing plans to Turkel 6/9 for discussion, and we were all targeting 7/1 for a CD set we could use for the building permit submission. While this was in process we were weighing timber vs helical piles for the foundation system, discussing MEP design vs design/build, and looking more closely at the window package (SD did not give much or any consideration to air flow through the home). We were also working on a Turkel provided “builder specification” that would be used to cost out the non-package portion of the project and select a local builder.

7/1 – DiSalvo provided a foundation permitting set of drawings. At this point engaging a local builder and engaging a pile driving firm were the critical path items, so we elected to wait for a full set of plans and make a single permit submission.

8/3 – Submitted plans for permitting. Norwalk lost the plans and gave them another set a week or so later.

8/22 – Met with planning & zoning to go through their feedback, which was small inconsistencies between different drawings, need to label this and that, etc.

8/29 – Submitted updated drawings for permitting.

9/1 – Planning and zoning pointed out a few small mistakes/inconsistencies.

9/3 – Submitted updated drawings for permitting.

9/13 – Zoning permit issued.

9/15 – Building permit issued. So 13 months from signing contract with architect we had a building permit!

As we got into costing out the non-package part of the project, the main floor deck included about 355′ of steel beams (main floor deck roughly 49’x46′), about 110′ of which were under moment frames. And grade beams were mostly #6 rebar, which is unusual for residential construction. Turkel had another structural engineer that thought the home could be built without any steel, and DiSalvo said they could reduce steel a bit but the downside to that was additional concrete piers and steel to wood connections. Given where we were in the project re-doing the structural work was not an attractive option, and Turkel ended up moving the main floor deck and steel into the package, which was coming from a fabricator in Canada.

Turkel works with several different fabricators, and our purchase order indicated they would be using TekkHaus (no website any more, maybe they were acquired, or went out of business, not sure). For the steel value engineering Turkel worked with Pacific Truss Homes, so they were added to the mix with DiSalvo. The value engineering eventually went nowhere and we ended up back with TekkHaus for fabrication.

10/14 – Received final version of foundation plan with pile locations (as a result of coordination with package fabricator adjustments to the permit set were made).

2/16 – Complete construction set issued. Included additional detailing from the permit set, and incorporated a lot of work on the window package, window locations and sizes, and instead of just Marvin Contemporary went with a combination of Marvin and Integrity, more on that in a separate post.

4/20 – Final update to construction set. I think this was mainly window detailing updates.

demolition of the existing (teardown) home

Before we closed on the purchase of our lot we had an Big East Environmental check the existing home for asbestos and we also had them check to see if there was a buried oil tank (the existing home was on city gas, but it was not much extra to check for underground storage tanks so tacked that on to the scope). Big East found some asbestos so that would have to be abated before the home could be demolished (115 sqft of linoleum tile, 20 sqft of bathroom tile, and 40 sqft of roof flashing). Not a big deal, some cost and time, but no barrier to closing.

As we started the design process for the new home with the architect we discussed the demolition of the old home, and they “highly recommended” not doing that until a building permit was secured, in order to avoid unpleasant zoning changes. We did a little homework on zoning, I think I might have also stopped in to talk to the local planning & zoning people, and the new home was going to be larger and tighter to setbacks than the existing home, so we ignored the architect’s advice and proceeded with the demolition so that we could have things moving forward in parallel. For example, to conduct borings for soil tests we needed to have the demolition complete, and to design the foundation we needed the soil evaluation done. It also seemed to be hard or impossible to get liability insurance with a vacant (uninhabitable) home on the property, whereas vacant land would be covered under existing liability we already carried. We didn’t get our building permit until almost a year later, so glad we didn’t wait …

So shortly after closing on the lot we picked Terzian Trucking to do the demolition and engaged Homeguard Environmental to complete the asbestos abatement. Once the asbestos was removed Big East came back out to complete a final inspection and provided us with a Certificate of Visual Clearance and a copy of a notification they had sent to the CT Department of Health.

The demolition process in Norwalk is straight forward and probably typical. Before permitting the demolition you need to publish a notice in a local newspaper, notify your neighbors via certified mail, and post a sign on the property.

To get the demolition permit you also need a tax clearance certificate, disconnect letters for all utilities, sign off from the historical building people, asbestos clearance info, and the demo contractor needs to provide his license and proof of insurance. Surwilo Contracting handled sewer and water disconnects, coordinating with the Norwalk DPW and the local water utility. Water main was on the other side of the street, they went in through lawn and disconnected the old 3/4 line (maybe iron?) at the main. Sewer was disconnected pretty close to the street ROW line in our yard, they ran a video camera in to check remaining lateral out to the main and then capped it. 6″ PVC was in good shape so all we would need to do is reconnect. For gas the utility, Eversource, removed the meter and disconnected the line at the main, no cost to us. Electric the utility came out and removed the meter and the overhead line.

The actual demo was completed in just a few hours. No basement but a few concrete footings that were a little work to get out. Building department came out to take a look and then we received a Certificate of Compliance to close out the demolition permit.

interior door hinges

Interior doors we went with pre-hung 1 3/4″ solid core birch slabs, all 7′ high, mostly 32″ wide, 36″ for utility room and main passage from the laundry/mud room. Hinges were normal butt hinges in satin nickel, looks like they were Hager hinges. Prepped for radiused hinges and a single standard bore. Doors were a little over $200 per copy (strangely the one 20″ door for a linen closet was the most expensive at $263).

I didn’t realize the hinges would squeak and spew out black graphite, I would have happily sprung for ball bearing hinges to avoid both of these problems. Former problem is fairly easily addressed by banging the pins out, cleaning things up as best you can, applying white lithium grease to the pins, and banging them back in. Latter is only bad if the hinge is not tight to the jamb, which ours mostly are not. I don’t know how long it will take the graphite to dissipate, and I am not sure how easy or hard it will be to try to clean things up (seems people suggest using trisodium phosphate or Krud Kutter).

towel and grab bars – block before you rock

It did not occur to our architect, builder, or any of the subs to mention that it might be a good idea to install blocking for cabinetry or bathroom towel/grab bars before sheet rocking. I think it would have been a very good idea to do this. Not such a big deal with cabinets, because not too hard to hit studs with those, but quite important for grab bars, which are likely to not land on studs, and also maybe for towel bars, though loading for those will not be too bad.

So I didn’t want to cut the walls open to install blocking for towel bars. Our bathroom fixtures are all Hansgrohe’s Axor Citterio M in satin nickel. Hansgrohe bars look OK but are expensive and long lead time and squared off. We decided to go with Valsan’s Porto line, which has round rods and is modern looking and available in a satin nickel, moderately priced and readily available.

To mount I consulted the many photos I took before we sheet rocked and used my handy neodymium magnet stud finder, along with wall panel shop drawings, to figure out what was where. Where I could mount to studs I used 1.5″ GRK cabinet screws. Where I was not going to catch a stud I used Everbilt hollow wall anchors, I think these are considered to be molly bolts and seem to be the best way to secure things securely to sheet rock. Our sheet rock is all 5/8″, so needed the longer anchors for this. I think the shorter anchors may have worked, but the boxes for same call out max thickness of 1/2″. Home Depot had these anchors (Lowe’s did not, nor did a good local hardware store).

Theoretically you can just drive these anchors through the sheet rock, but you would have to pound the heck out of them for this. Our sheet rock is already poorly fastened because studs were all over the place and driving these through would have caused a lot of damage. I already popped a few sheet rock screws fastening the towel bar fitting to studs. I forget what drill size I finally used, but I worked up to a size where it was pretty easy to tap the anchors through the hole. No problem with the anchors spinning as they were set, the barbs held plenty well in the new sheet rock. I would not want to hang anything hugely heavy on sheet rock, but a couple of towels on 5/8 should be fine. I put of a couple of hotelier racks like this too and am not too worried about them either.

No grab bars for now. If those don’t happen to land on a stud I think we are cutting the walls open to block for those. We’ll wait until we are a bit older …

pocket door (slideset and cavkit assemblies from ezjamb)

We’re not big fans of pocket doors, but it seemed like the best way to implement a door to the commode in the master bath. I had looked at EZJamb products for doors without casings but decided to go down another path, more on that in another post, but I thought the SlideSet would reduce installation labor and be high quality for this pocket door, and that the accompanying CavKit would provide modern/clean finishing trim with minimal fuss.

It is not possible to order from EZJamb directly and no local building supply company really knew anything about their products. RO requirement is 2x door width + 1/2″ and door height + 3″, and we prepped opening for a 32″ x 84″ (x 1 3/4″) door. The SlideSet marketing brochure says the kit is available for 30, 32, or 36 inch wide by 80, 84, or 96 inch high doors (1 3/4 only).

Despite clear direction the first supplier decided to order a kit for a 30″ wide door, which we did not discover until the kit was ready to ship about a month after we ordered it. This same supplier goofed on jamb width for a couple of other doors we had ordered, forcing us to cut them down, and ordered an entry door I didn’t want, so I was not too sympathetic and I ordered another assembly from a local supplier that EZJamb recommended (but which local supplier didn’t really know the EZJamb products). So then it was another month plus to get the correctly sized kit, but it arrived with some damage and the supplier refused the delivery. Another couple of weeks and the repaired assembly was delivered. During that process I asked to see a drawing of what we were getting, it indicated kit was for a 2×4 plate/wall, I had asked for 2×6, we actually received the latter, strange that they didn’t know what they sent us.

So the supplier of the kit also got us a slab to use with the kit, solid core birch, I asked for 32x84x1.75, in their defense they said they had highlighted that they only stocked beveled slabs, but the one we got was about 31.5×83.25 and was of course beveled. So that door (and the 30 inch slab that was delivered before the first SlideSet order goof) went in the dumpster. Another local supplier was able to get a slab that was the full 32×84 size (though also beveled), so we got that on site.

Next challenge was to find someone to put this thing in. First carpenter spent half a day looking at it and gave up. The basic instructions are OK, but there is very little detail in them about the rail system and fastenings. Next carpenter set the assembly frame in the rough opening but didn’t think fastening to the MDF top edge of the solid core door would work. Solid core doors are heavy, this one probably pushing 100 lbs, and the fittings that fasten to the track cars mount into a groove that needs to be routed in the edge of the door, he thought screws would pull out. Carpenter #3 said no sweat and got the slab installed in the kit, took two good guys a few hours. I went and got some long coarse thread screws and some glue for the job. Carpenter said there should have been a header above the RO and that we may have an issue with the track sagging.

Here is the install with the closer cap sunk into the sheet rock to the left.

Soft close mechanism works great but the rolling action is pretty noisy. These wheels a hard plastic, I think other rails (architect called out a Johnson 2060 or equal) may have softer wheels and run more quietly. The SlideSet and CavKit were just under $1500, it probably would have been quicker and cheaper to use the Johnson kit and have the carpenter do the framing.