The number of new cases of Alzheimer's disease and other dementias in Canada will double in the next 20 years. The Alzheimer Society of Canada says one in 13 people over the age of 65, and one in three over the age of 85, experiences dementia.

Housing family members who have Alzheimer's disease or another form of dementia is a challenge, as you balance the safety and comfort of your loved one with their need to feel independent. Designing or renovating a home for people living with dementia goes beyond adding safety locks and grab bars -- it must also provide a flexible framework that can change along with the person's needs.

Canada Mortgage and Housing Corp. (CMHC) recently produced a revised edition of Housing Options for People Living with Dementia, which was first produced in 1999. It uses the Alzheimer Society's guidelines for person-centred care.

"Dementia does not diminish a person but changes their capacity to interact with their environment," says the guide.

Upholding the dignity of the person living with dementia is key. They should be included in any discussions about renovating or making changes to the home.

Research has shown that people living with dementia in a home-like, familiar environment show less agitation, aggression, depression and social withdrawal than those in a more institutional setting, says the guide. It says people who have more privacy and are allowed to personalize their bedrooms have less agitation. Caregivers should avoid changes to the home that make it look like a hospital room or institution.

"Keep it familiar, striking a balance between safety and independence," says the Alzheimer Society. It says too many restrictions can make it difficult for the person to take part in daily activities and can seriously affect their self-esteem.

Changes should allow them to remain as independent as possible, "rather than promote passivity, dependence, boredom and even depression," says the guide. "Promote safety in an unobtrusive way for both persons with dementia and their caregivers. For example, working towards a balance between safety, security and independence may involve limited exposure to potential hazards (such as removing sharp knives from a cupboard) and encouraging activities that safely promote independence and well-being (gardening or cooking with a caregiver present)."

The Alzheimer Society says to keep in mind some of the issues that face those with dementia, including "decreased balance and reaction time; visual perception problems; physical limitations that make it more difficult to walk; memory; judgment and insight."

As the disease progresses you may need to make ongoing changes to the home. Adapt the person's activities to their abilities. For example, the Alzheimer Society says a person who enjoyed woodworking may no longer be able to use power tools but they may still be able to nail, sand and paint in the workroom.

The CMHC guide says that many people living with dementia spend a lot of time looking out the window, so try to make sure there's something to see to enhance the quality of life. Make it easy to look out a window on to a garden or another area where things are happening, such as a parking lot. Maximize opportunities to use a patio or balcony.

Many of the modifications that must be made for those living with dementia are the same as in any barrier-free home -- wider doorways, safer stairways, adding handrails, no-slip floors, grab bars in the bathroom and good lighting. Some other modification may be necessary depending on the needs of the people living there.

But don't make changes for the sake of change -- the rooms should be recognizable and familiar and unless something presents a problem or an obstacle, it should probably be left alone. Before making a modification, ask what impact it will have on the person, what risks are involved and what is the worst that could happen. Try not to make too many changes at the same time.

The CMHC guide says low-pile carpets are the best choice for floors, because a shiny floor can cause glare and be confusing or disturbing for those living with dementia. It says floors should be one consistent tone that is the same between rooms.

Threshold strips can be perceived as a step so they should be avoided. Doormats that are dark may look like a hole in the floor, so they should be the same tone as the floor. Any kind of flooring that has speckles or sparkles can also be confusing and people with dementia may try to pick up the specks, says the CMHC guide.

A handheld shower head is preferred over an overhead waterspout, which some people may find frightening.

Consider installing wardrobes with an open side or glazed door because many people with dementia can't remember where their clothes are. Signs on drawers also help.

In the living room, don't make the TV the focus of the room. Some people with dementia get alarmed by reflections on the screen when it is turned off. If possible, cover the TV screen when it's not in use.

Wandering is an issue for some people with dementia. Some simply wander around the house, while others may try to go outside.

Solutions range from installing motion lights to ensure safe wandering at night; to installing locks and alarms. The Alzheimer Society recommends that the person wear a MedicAlert Safely Home bracelet in case they get lost.