About Your House
Renovating Your Bathroom
Renovating your bathroom is a great way to add value to
your home — both for your family’s daily living and for future
Before you decide to go ahead with a renovation, it’s
critical to have a good idea of any underlying problems that
could cause unwelcome and costly surprises. Taking time to
find problems before you start your renovation will save you
money, protect the indoor air quality and preserve the
durability and structure of your home.
A bathroom renovation is one of the most common home
improvement projects. Bathroom renovations come in all types
and sizes—from a simple update of the flooring, to enlarging
the room and replacing all fixtures and finishes.
Your project is unique, but your reasons for renovating
will probably fall into these common categories.
- Size and design — The room may be small
or poorly designed.
- Fixtures — The fixtures may be
outdated, small, hard-to-clean, leaky, cracked or
- Structural — There may be problems that
require structural changes or repairs.
- Moisture — Excessive bathroom moisture
may have deteriorated the bathroom surfaces, affected the
indoor air quality or jeopardized the structure of your
- Plumbing and electrical — If your house
is 30–40 years old, the plumbing and electrical services may
be outdated and need upgrading. Houses built prior to 1950
often have lead piping that may pose a health hazard.
- Heating and ventilation — Bathrooms are
often cold because of poor insulation or poor heat delivery.
Ventilation is often inadequate, non-existent or causing
secondary problems that need to be fixed.
Renovating is an ideal time to make your house healthier
for you, the community and the environment. When assessing
your renovation project, be sure to consider the five
essentials of Healthy
House as a System
A house is much more than just four walls and a roof—it’s
an interactive system made up of many components including the
basic structure, heating, ventilating and air conditioning
(HVAC) equipment, the external environment; and the occupants.
Each component influences the performance of the entire
system. A renovation provides an opportunity to improve how
your house performs.
Bathroom renovations often include changes to HVAC
equipment that can improve moisture management in the house.
Structural changes may improve air sealing and insulation,
resulting in increased occupant comfort and house
Before you start renovating, you’ll want to think about
your bathroom, your needs and your budget. Look carefully for
signs of deterioration and the possible causes. This will save
you money and also help you to be better informed if you’re
dealing with contractors. Reflecting on your project will also
help you to decide whether you need the services of a
professional. Being unsure of what needs to be done,
recognizing that the job is very complicated, or that you
don’t have the time or energy to do the work, are good reasons
to hire a professional renovator.
|Size and design|
- What aspects of the current bathroom need to be
- Is the layout convenient? Is there enough storage?
- Does the bathroom meet the needs of everyone in
the household, including anyone with special needs,
extended family and guests?
- Choose a design option that meets your existing
and future needs. This may be a simple renovation to
replace fixtures or a complex project to change the
layout, enlarge the bathroom or add an extra bathroom.
- The layout may not be flexible enough to meet
existing or future needs for space and storage.
- Also, the layout may not be suitable for anyone
with special needs such as wheelchair accessibility.
- Are the fixtures or seals damaged, cracked or
- Is the styling outdated?
- Are fixtures water and energy efficient?
- Is there often condensation on the toilet tank?
- Replace or repair damaged, cracked, leaky fixtures
- Choose fixtures that enhance the appearance of
your bathroom while conserving water and energy.
- Install an insulated toilet tank to keep the tank
- Plumbing leaks will continue to cause damage to
finishes, the house structure and will promote mold
- Outdated fixtures usually mean higher energy and
resource costs. New toilets can save more than 70% of
water per flush. Low-flow showerheads can save 60% on
water usage. Compact fluorescent light fixtures are
four times more efficient than standard incandescent
- Cold toilet tanks are prone to condensation that
leads to moisture problems.
- Which walls are load bearing? Will they need to be
cut or removed as part of the renovation?
- Are there any cracks, slopes or bulges that might
mean that the floors or supporting members are
deteriorating or inadequate?
- Are the walls deep and strong enough to allow
installation of grab bars, new windows, plumbing or
- Are exterior walls, floors or ceilings cold or
drafty? Is it noticeably cold while taking a bath?
- Assess the structure carefully. The proposed
renovation must either fit the existing structure or
the required structural changes must be possible.
Expert help may be needed.
- Repair or upgrade structural elements so that they
are able to meet expected loads.
- Install structural blocking or backing as needed
for grab bar installations. Build out walls to
accommodate new windows, plumbing or ducts.
- Insulate and air seal the exterior wall, ceiling
or floor assemblies to provide warm surfaces and a
- Improper structural changes, new loads or
proceeding with changes that stress the structure may
cause wall settling or collapse.
- Ignoring the underlying cause of bulges, slopes or
cracks can result in recurring problems.
- Installing structural blocking for grab bars after
renovations are complete will cause expense and
disruption. Insufficient wall cavities may limit or
prevent installation of windows, plumbing or proper
- Poorly insulated exterior surfaces, poor quality
windows or poor air sealing will result in cold
surfaces that cause discomfort and are prone to
condensation, which can lead to mold growth.
- Are any finishes moisture damaged?
- Are there water stains or visible mold growth on
- Is there any blistering or peeling paint?
- Are any surfaces buckled, swollen or rotten?
- Is there any chipped or cracked grout or caulking?
- Determine if moisture comes from building leaks,
plumbing leaks or high humidity. Fix the causes of the
deterioration—for example, repair roof, wall or window
leaks. Repair or replace all water damaged or
- Clean up visible mold growth following CMHC
- Ventilate to control excess humidity.
- Maintain grout and caulking to prevent water
access to cavities.
- Choose low-odour, low-toxicity materials and
finishes to minimize the effects on indoor air quality
- Unresolved water problems will cause renovations
to deteriorate quickly, whether the water comes from
building leaks, plumbing leaks or the high humidity
generated by bathroom activities. Leaks may contribute
to mold growth and result in serious IAQ problems.
- Hiding moisture damage behind new finishes can
cause deterioration and mold growth to continue.
- Are there any signs of leaks such as mold growth,
soft drywall or rotting materials?
- Is there sufficient water pressure?
- Do the pipes make a banging noise (water hammer)?
- Does water drain slowly? Are there any unusual
noises or smells coming from the drains?
- If the house is pre-1950, are there any lead or
galvanized steel waterpipes?
- If the house is more than 30 years old, is the
electric service and wiring safe and adequate?
- Is the lighting adequate, providing good overall
and task area light?
- Repair any plumbing leaks. Upgrade plumbing to
meet current codes and the needs of new fixtures.
- Install larger diameter water pipes to allow
greater flow or pressure balancing valves.
- Provide an air cushion to eliminate water hammer.
- Ensure that the drainage system is sufficiently
vented and that proper traps are installed.
- Replace lead or corroded metal pipes.
- Have an electrician inspect the electric service
and wiring. Repair and upgrade electrical service and
wiring if needed. Equip outlets with ground fault
circuit interrupters for safety.
- Update lighting so that it is adequate and energy
- If plumbing problems aren’t repaired,
deterioration will continue and mold will grow.
- Poor water pressure and water hammer problems will
- Plumbing problems such as slow drains or smells
from poor venting will still be annoying, may get
worse and be a source of poor IAQ.
- Lead piping and corroded metals can contaminate
water and leak.
- Electrical service, wiring and outlets may be
inadequate or unsafe for increased loads (e.g.,
whirlpool tubs or space heating). New lights or
outlets may overload existing wiring.
- Lighting may be poor and use energy inefficiently.
- Is the bathroom cold?
- Does condensation form on windows, mirrors or
- Is there a stale, musty smell?
- Is there an exhaust fan that doesn’t work? Does
the fan vent directly to the outside? Is the duct
insulated where it passes through unheated spaces?
- Provide an adequate heat source.
- Ideally, install a whole house ventilation system,
including a heat recovery ventilator.
- If the whole house system is not an option,
install a quiet exhaust fan with adequate airflow
capacity to handle excess humidity. The fan should
have a sound rating of two sones or lower and must
vent properly to the outside.
- Problems can arise if heating, ventilating or air
conditioning (HVAC) needs cannot be met by the
capacity of the services available. The heating supply
must be enough for comfort. Proper ventilation is
needed to control excess humidity and to remove indoor
- HVAC problems affect how the entire house
functions as a system.
- Correcting structural flaws, fixing leaks and making
sure that all services are adequate before renovating will
make renovations look better, work better and last longer.
- Using low-odour and easy-to-clean finishes will improve
IAQ and help prevent mold growth.
- A warm, comfortable, attractive bathroom can contribute
to a safe, relaxing lifestyle.
- A bathroom renovation typically offers a 64-71% return
on your investment, meaning increased value of your house
Skills to Do the Job
A homeowner with good fix-it skills may be able to do some
of the work including:
- Removing old fixtures.
- Gutting old wall surfaces.
- Removing non-load bearing walls.
- Fixing roof or window leaks.
- Insulating, installing a vapour barrier and air sealing.
Serious structural work may require the services of a
professional renovator. You’ll also likely need an electrician
for any new wiring, a plumber for the plumbing work and a
heating contractor to install or move heating or ventilation
outlets. You may want to hire tradespeople to do the
structural work, roofing, window repairs or installation and
any exterior wall repairs.
Use the Bathroom Assessment Worksheet to record the
present condition, any problems in your bathroom and
||Present Condition /
||Options or Upgrades
|Ceiling and Finishes
|Walls and Finishes
|Floor and Finishes
|Electrical Service and Wiring
|Heating and Cooling
Costing Your Project
The cost of essential repairs will depend largely on the
deterioration of the existing structure and how much
professional labour is needed. Use these categories when
costing your project.
Other Useful Information From Canada Mortgage and Housing
Although this information product reflects
housing experts’ current knowledge, it is provided for general
information purposes only. Any reliance or action taken based
on the information, materials and techniques described are the
responsibility of the user. Readers are advised to consult
appropriate professional resources to determine what is safe
and suitable in their particular case. CMHC assumes no
responsibility for any consequence arising from use of the
information, materials and techniques