Having just got through the Mechanical portion of the construction of our warehouse, I feel like there is a lot of information that is crucial and really important for future reference.  In all, this is probably the part of the job that is filled with the most grunt work.  It is messy and for the most part thankless work that requires lots of lower back strength and willpower.  There are times that I wanted to quit for the day, but what served the process really well was to persevere and make it to the end of the day.

Like every major step of this process, I have learned much about this portion of the construction process, and I have completed a chart below that helps to summarize the key learnings.

1. Pick the Right Mechanical Contractor:  This is likely the most obvious item on this list, but the one that needs the most time and attention before things start.  Make sure you work with a mechanical contractor that is willing to work with you throughout the process.  Things like are they going to dedicate their time to the job, are they using 1 man or a 3 man crew, or even how many days of work do they expect the sections to take.  Knowing some of the details, will help your expectations be in line with reality
2. Make sure you look for ways to cut costs, and make sure to negotiate these reduction in fees can go into your pocket and not your mechanical contractor:  By this I mean, if you want to change something, like a trade waste interceptor or location of a drain, the expectation is that they will not overcharge you for this.  You will need to talk about items that could change down the road.  We have changed a lot of stuff.  Hot water tank, locations of drains, flow meter, trade waste interceptor, and a bunch of other small stuff.  What is important is that we talked about this early on in the process, and we have hammered out a good deal with these kinds of things.
3. Get ready to dig:  You can hire someone to dig, and the cheapest we could find labour through someone else is $25 per hour all in.  If you want to hire someone off the street, they are not going to be covered by WCB, which is a big no-no, and more importantly if something happens, you are screwed.  So this means that to save money you are going to be working that shovel.  Between Iain and I, we spent over 150 hours combined on the shovel, which by my quick math has saved us about $4,000.  It doesn’t seem like a lot, but in the grand scheme of things, that is $4,000 more we have for something else.
4. Get the right size trade waste interceptor:  Getting a TWI too big or too small will mean trouble no matter how you cut it.  If you get one too large, you won’t have to clean it out very often, but it will be a pain in the ass to install into your floor.  A TWI that we looked at was over 11,000 lbs, which had a list of issues when you were trying to install.  If you get a TWI that is too small, it might be a lot easier to install, but you will be calling every month to get it cleaned out.
5. Use a plastic trade waste interceptor:  We ended up going with a plastic TWI which solved all our problems.  It was less expensive that a traditional TWI and it was a lot lighter than a normal TWI, at only 350 lbs.  In fact, it only took of us to lift it in the hole.  Make sure you make the decision on this early in the process.  You don’t want to hold up the process with fretting about a decision.
6. Get drawings from your Structural engineer early on in the process:  I have written a full post about our issues around a structural engineer, so if you follow my blog you know well our issues with this area.  In short, get your structural engineer on board early, and make sure you agree to a timeline of what needs to be completed and when.  If your expectations are met, you are golden.  If your expectations aren’t met, then you need to take action.  At the end of the day, it is your ass on the line.
7. Get lots of quotes:  There is more to this aspect of the process than just the mechanical work.  There is laying out of the floor plan, concrete cutting, concrete removal, digging, grading. forming for concrete, installation of rebar, drilling of holes for rebar, packing holes, filling with dirt, compacting, and likely more and more digging.  You can choose to do some of this on your own or you can pay someone to do it all.  Our advice, save some money and do it yourself.
8. Don’t forget about the flow meter:  I can’t say that I know too much about this, but definitely the city of Vancouver requires a flow meter, located after the TWI, to measure the amount of effluent you pass into city sanitary sewers.  Make sure you include this in your plans when you dig, so that you aren’t left doing additional digging afterwards like we did.
9. Upgrade the water line:  We didn’t need to put an upgraded water line in, but you will likely be doing this through this part of the process.  I can’t say I know anything about this, but I have heard it costs about $10,000 and up depending on how far the line needs to go.  I am sure its no harder than any of the other digging that happens, it just adds to the amount you are doing.
10. Tamp the ground excessively:  It is better to tamp the ground more than less, so that you have less movement of the substrate down the road.  This is pretty simple, but it is easy to overlook as the whole process is so grinding.  Just do one extra pass to make sure all goes in well.
11. Cover up areas near the concrete pour with plastic:  Pouring concrete is a dirty, messy job and the guys that do it, don’t really care about anything other than getting the job done.  We were given the advice to cover areas around the concrete pour with plastic, so that the spray of the pouring wouldn’t get everywhere else.  We are really glad we did this, and it saved us a lot of headaches.  The few areas we didn’t cover we wish we did, as they are sprayed with concrete and we can’t get it off.