Ground Floor Roof

Day 210
November 17, 2012

Ground Floor Roof !
While walls come-up quickly and show visible progress, it takes a bit of time to get roof completed. For starters, it is advisable that all walls progress at more or less equal pace as roof construction can not start till all walls are up.

In our house, we have wirecut bricks in certain areas and as I mentioned in my earlier post they take a while to procure and once procured take further time to lay them in place. One of the reasons for delay is it requires specially skilled mason to handle cementing of wirecut bricks.

Additionally, we had specific pattern to arrange them in. A couple of the patterns are shown here. Patterns make the wall come alive; they however cost a bit more both in terms of quantity of bricks as well as time taken to lay them so they are appropriately aligned.

As a layman, these delays were not obvious to us at the start.

Having gone through the process we now know that laying wirecut bricks takes twice as long and laying wirecut patterns takes thrice as long as the normal bricks. For us, these added 3-4 weeks to overall schedule.

Obvious advice is to be paranoid about each task - ask stupid questions as that'd uncover potential surprises that can be avoided.

Roof height

Unless a house has tall ceilings, most people don't pay attention to how high the ceiling should be. They usually go with the standard 10 or 10.5 feet height. And so did we. Our architect, however, had designed drawings with 11 feet height. As the walls were getting constructed, I actually felt 11 feet looked too monstrous in some rooms and was reluctant to go with that. Being the first-time house-builder it is very hard to know whether to stamp your opinion, or go along with architect's design. Do some research on advantages and disadvantages to find an answer that is right for you. Here is a quick summary of pros and cons of 10 feet vs 11 feet.

• Taller ceilings give feeling of spaciousness. Rooms look a lot more elegant. 
• Taller ceilings cost more and take longer to build.
• Taller ceilings in a multi-level house mean more stairs to climb.
• Taller ceilings help with keeping room cooler as hot-air stays at or near the roof. 
• Taller ceilings provide larger storage space should you construct wall cabinets. 

We decided to go with 11 feet and after the roof was casted, I was thankful to have listened to architect and contractors' advice. 1 feet makes a huge difference in feeling of spaciousness and elegance.

Electrical design

As soon as the roof is cast, a number of activities - electrical, window frames and shutters, plastering, etc. can happen in parallel. By now, your architect should already have finalized furniture layout and should be talking to you in terms of electrical layout.  It is critical for home-owners to freeze both these items at this stage as without them none of the other work would proceed.

For example of electrical drawings, here are a couple of samples from our house. Undoubtedly, there will be a few iterations to get these right. So, allow yourself a bit of time on how you'd live around your new house. That'd determine number and type of lighting you'd need. Lighting is one of the crucial aspect to set ambiance so you want to make sure to not rush it.

A couple of rules that we followed for electrical layout

• Be liberal with points - I have observed that more often than not after the house is done you realize need for additional plug-points. While this costs a bit extra upfront, I'd much rather not have to open-up electrical (or avoid having power strip everywhere) after house is done
• One open plug-point per wall is a thumb rule - Again, calibrate according to needs of each room
• Avoid too many types of lights, we picked a type (e.g. wall mount) and repeated that across the house. 
• Avoid more than 6 switches in a switch-board - Hard to remember which switch is for what and looks kinda ugly.

Roof construction:

1) Order materials - While this is an obvious thing, some times procurement adds delays. In our case, we needed long-enough "bamboos" for 11 feet ceiling and those were not readily available. Ensure that contractor orders steel, cement, sand, aggregate, etc enough in advance so that it arrives in time.

2) Setup centering - This is where maximum time is spent. Workers setup metal sheets supported by the bamboos. Depending on roof area this can stretch over in days or weeks. Thumb rule is to expect 1 room per day. If you have stairs, those are also done at this stage. This is because they need to ensure the leveling of stairs occurs at the same time as centering is set up.

3) Do form-work - Once centering is setup, they lay-out steel rods that will hold the roof together. This is done in usual mesh pattern. For about 1000 square feet roof, it took 1-week to set this up.

4) Layout electrical conduits - Contractor will identify electrical drop points in each room. These are essentially points from which electricity flows into the room. It is good to have electrical layout finalized at this point although if it is not, contractor will identify a few default points.

5) Structural inspection - One final step is to get structural engineer to approve construction. Structural engineer is the one your architect would have consulted to structurally build your house. His approval is critical to ensure house meets the safety standards he'd have set in place during design.

6) Pour cement - Pretty straight-forward step. I was surprised that this takes usually 4-6 hours. My contractor suggested to manually make cement so as to have better control over proportion of cement, aggregate and sand. However, market is also full of ready-to-pour cement mixes as well. Go with whichever you (or rather your contractor) feels comfortable with. It is important that whole roof is done in a day to allow roof to solidify at once.

7) Remove centering - Once cement is poured, make sure it is cured regularly. This allows cement to bind really well. Curing happens for few (2-4) weeks. Typically, centering stays for support for about 6 weeks.

8) Payment - My contractor insisted to have fewer but bigger payments and that model worked very well for us. My second payment was when ground floor roof was casted (first was when plinth level had reached). My BOQ (bill of quantity) is also structured for each phase (Plinth, Ground floor roof, First floor roof, etc.) This model allows me to easily verify actual versus estimate in BOQ much more easily. Every time bill is raised, architect also needs to verify quantity of material used vs estimated and doing it less frequently makes his task also easier and more efficient. Any way, point of this bullet is to verify how you are tracking with respect to estimated cost and justify any deviations. 

9) Schedule and Quality review - Final check-point at the end of this phase is to review schedule and quality with your architect and contractor. This must be not just at the macro-level analysis of big-picture items, but rather a finer-level analysis.. For example, what factors contributed to delays, what compromises led to aesthetics or structural inadequacies. By now, you'd also have had a good rapport with both architect and contractor to unequivocally communicate action plan going forward. My advice is actively ensure that mistakes are not repeated, don't assume that someone once told will henceforth do the right thing.