Page 493 - 2018 National Home Improvement

2018 National Home Improvement Estimator, All Rights Reserved Page 394

Water Heaters
Some older homes may still have domestic water coil systems in the furnace. That may provide enough
hot water for cooking and bathing during the heating season. During summer months when the furnace
isn’t running, a regular water heater will be required. A gas water heater for a three-bedroom home
should have at least a 30-gallon capacity, though 40 is the current standard. An electric water heater for
the same home should have a 50-gallon capacity.

Pricing Plumbing and HVAC Repairs
Home improvement contractors usually subcontract heating, air conditioning, and plumbing work to
specialists. Plumbing and HVAC subcontractors usually quote the total installed prices only, without a
breakdown of material and labor costs. However, to improve the data’s versatility, this chapter provides a
breakdown of the labor and material costs.

Framing for Plumbing and HVAC Improvements
Installing new heating duct, plumbing stacks, drains or water piping will usually require alteration of the
framing. Plumbers and HVAC installers will arrive on the job site with all the tools needed to cut away
structural wood framing. But a carpenter may not appreciate the result. Caution your plumbing and
HVAC subs to avoid cutting if possible. When critical framing members have to be cut, have a qualified
carpenter add stiffeners or supports.

Cutting Floor Joists
When a floor joist has to make way for passage of a stack or vent, install headers and tail beams (as in
Figure 14-1) to reinforce the area around the joist that has been cut.

Figure 14-2 shows how to pass water pipe or conduit through a joist. The hole can't be any larger than
2" in diameter. Edges of the hole must be at least 2-1/2 to 3" from the top and bottom of the joist. You
can also cut a notch at the top or bottom edge of the joist. But the notch should be in the last quarter of
the span and not more than 1/6 the depth of the joist. If a joist has to be cut and you can't comply with
these rules, add an additional joist next to the cut joist or reinforce the cut joist by nailing scabs to each
side.