Monday House, part ix, heating and plumbing


Huge progress was made in the Monday House this past week. In part, this is because the work force doubled from the usual crew of four carpenters. Add in two electricians, and two plumbers, and lots of visible pipes and wires …

The general contractor installed the ductwork. The duct runs are complicated as the route has to planned through inside walls and modern houses don’t have many of those. Outside wall cavities need to be filled with insulation, and because of the stone foundation, ductwork cannot go up near the outside walls. So there is lots of pressure to make the best use of inside walls. And it has to go up the first floor walls and end up between joists, or continuing up through bedroom level walls, or run through bulkheads, to get to its destination. And you cannot go through the nice new LVL beams.

The short wall separating the living and dining areas had to be “doubled up” (2 – 2×6 walls plus a gap between them) to fit in all the ducts taking conditioned air to the rooms and returning stale air to the equipment in the basement.


Here’s the short wall between the kitchen and dining room:


The left-most duct goes into a bulkhead running behind the new LVL beam. The second-from-left duct runs through a new bulkhead in the dining room. Bulkheads have to planned very carefully since they are visible. In this case, bulkheads will wrap all around the dining room ceiling for aesthetic balance, even though two portions won’t actually have any ducts in them.

Bulkheads are either something that you notice, and therefore are important, or you don’t notice them. Most new home mass builders just put them in where necessary and don’t “balance” the look,hoping new home buyers wont notice. Of course, the builders try to stick all the ducts between the joists to avoid the cost and aesthetics of building bulkheads, but sometimes that isn’t possible.

In the photo below, the space between the spot where the ducts go through the floor, to the exterior wall on the left, is above the rubble stone foundation. Wiring might be fished up through here, but not plumbing or ductwork.


In old houses like this, originally there were no forced air furnaces (which were invented in the 1950’s). Instead, the coal furnace was in the centre of the basement and heated air rose up either through a big floor grate or through inside-wall ducts. Cold air returned to the furnace from large grates along the exterior walls. Most rooms had doors that were kept shut in the winter to trap body heat in the room in current use. Wearing a coat indoors was common, and long johns. And frost on bedroom walls was common at 7am.

The rising air / falling air pattern is reversed for forced air furnaces: warm air is pushed along by the furnace fan to appear beneath each window to fight drafts and cold; and cold air returns from ducts located in the centre of the house. However, when forced air furnaces were added to a 1902 house the ductwork was often not relaid, as it is extremely disruptive and expensive. So old houses remain drafty, especially when there is no cold air return inlets on the second or third floors — cooling air has to “fall” down the staircases creating a draft through the lower floors.

But in the Monday House, with all the walls opened up, all new ductwork is being installed using modern principles. Duct joints are screwed and taped, but not with the mis-nomered “duct tape”. The electronic setback thermostat will also likely turn the furnace’s air circulating fan on “low” for a few minutes once or twice an hour to gently rearrange the air the house, keeping each room and each floor evenly warm.


(above: duct delivering conditioned air to beneath a bedroom window, as seen from the room below. The duct runs under the joists, so a bulkhead will be built around it)

The old ductwork bits go off for recycling:



The picture below shows the plumbing drains in the kitchen ceiling to service the main bathroom above. The two “incomplete” sections of pipe leading toward round roles drilled in the floor are headed towards the shower and the bathtub drains, and will be “finished off” a bit later when the tub and shower components arrive.


The pic below shows those pipes in the bathroom itself. Note the shower hole to the left, the tub drain hole to the right. There are so many pipes they are going to construct a shallow false wall in front of them. Some pipes drain the waste water, others vent gases up through the pipe that sticks up through the roof. This prevents the drains from gurgling or sewer gas from entering the house.

You may recall the much earlier story of the old plumbing with the giant hole in it, that let gases into the house.   Some wall boards have been removed to facilitate running stuff inside those walls.



The electricians have a much more flexible material for installation, so they put their stuff in after the plumbing  and ductwork were put in. You can see here how much wiring goes behind a 3-switch in the bathroom, with wires leading in from the source, then out to various outlets and lights, or to the next switch location. The switch has to be a certain distance from water.


A plug goes near the vanity for hairdryers and shavers and all the stuff a modern household has in the bathroom. The electrician will install a Ground Fault Interrupter switch here. As soon as the plug detects any sort of problem, it shuts off instantly, preventing electrocution. The philosopher Thomas Merton died when he dropped his electric razor into the sink … Here too, you can see how she marked the stud GFI as a reminder of the type of plug to install.


Where plugs go on outside walls, the depth of the box reduces insulation value and opens a potential conduit for air leakage. So a bit of plastic was inserted behind the box. Before drywalling, all the walls will be wrapped in poly and taped to make an air tight and vapour tight seal around the outlet.


The pic below shows the upstairs hallway ceiling. There is a row of metal holders attached to the joists by the electrician. She will later insert recessed lighting fixtures (LED, of course) once the drywall is up. This row of recessed lights will give a clean look. She also put in wiring for a smoke+CO2 detector on every floor, interconnected so if one sounds off, they all do. And there is a hardwired smoke detector in every bedroom too.

There is new 1×4 wood “strapping” on the bottom of the ceiling joists to attach the finishable drywall to.



Meanwhile, downstairs, the carpenters installed a new header in the south outside kitchen wall. Part of the porch is currently behind this wall, but when that old addition is fully modernized and expanded, the owner may want to “open up” the kitchen wall to the southern light source and to connect with family in that room. So a new lintel was installed, allowing any combination of window(s) to be installed along the wall.


The lintel will prevent insulation from the wall cavity above from falling into the future opening. Since old studs and new studs are very different in size, the carpenters used old studs to build the supporting posts at each end of the new lintel. Any one, or even all three, of the remaining old studs under the lintel can now be removed or cut shorter or even right out in the future. Since the stove goes on the kitchen counter in this section, the owner is putting in a ceiling mounted fan hood.


This coming week will see electrical work all week, more plumbing, and yet more ductwork. The carpenters are finalizing their layout of bulkheads (across the ceilings) and chases (where ducts go up the interior of a room).