Home Design for a Key Lot

A key lot (or sometimes called a flag lot) is so called after it's shape.  This type of site is a lot located behind another property (or properties) with access via a strip of land.  The access strip is along the shank of the key (or the pole of the flag) then the lot opens out.

key lot

Here's an example.  You can see how there's a long piece of land to access the site.

key lot map view

I suspect this key lot was created from one of the existing homes that had a large back yard.  The main challenge is making sure that there's space for an adequate driveway.

Here's a satellite and slightly zoomed in view of the same key lot with the lot highlighted in yellow. 

I hope that gets across the idea of what a key lot is.

key lot satellite view

Another type of key lot is the outer corner site.

corner flag key site map view

And here's a zoomed in satellite view of the outer corner lot on the left.

corner lot flag site satellite view

So let's move on to the design considerations for a key lot.

Key Lot Design Considerations

Design consideration 1 - Shape and Size

It's pretty easy and quick to assess if a site is about the right size for your project.  With key lots the key is to take a long hard look at the shape. 

  1. How much of the quoted land area is taken up by the access strip?
  2. If you take away the area of the access strip, is the land an adequate size for your project?
  3. Because they're often squeezed in, the shape of key lots can be irregular.  Again, it's important to assess the buildable size of the key site.  And yet the irregularties aren't all bad.  They add character and can often be used for a useful function such as tucking away a garden shed or garbage bins.
  4. Key lots might have different definitions for the front and side of the site so be sure to find out exactly what the set backs are.  They might not be what you expect.  Find out more in the site zoning topic and check the site plan carefully.

Design consideration 2 - Street frontage

Typically with a key lot, the access strip is wide enough for the driveway only so the home itself effectively has little or no street frontage.

The approach to your home will have a very different feeling to a lot with street frontage.  If your access strip is long, think about how it can be made appealing using strategies such as lighting, landscaping, perhaps including some overhead elements.

The lack of street frontage can make it harder to find your home.  Think about how you can call attention to the access to your home.

Design consideration 3 - light and sun exposure

The orientation of a key lot and the surrounding buildings will determine the light and sun exposure available. 

Both of the sites below have openness towards the south which means that they will receive plenty of light.

You can see how the northern exposure on both sites is very limited.

key lot sun exposure

Design Consideration 4 - Privacy and Security

The minimal or lack of street frontage means there's privacy from the street at the front of both the homes.  While this makes it private, it also means that no-one from the street can see your home so there are security implications to key lots.

At the back, key lots tend to have lots of neighbors.  Both properties above have 6 or maybe more backyard neighbors.  This can mean that the rooms and in particular the yard at the back of the home are overlooked and you can have more than your fair share of backyard noise from all those neighbors.

But it's not all bad news.  There is also an advantage about being bordered by back yards.  There will usually be quite some distance between your home and most of the other houses giving it an open feel and letting lots of light in.

So, how will you make your key lot secure?  A gate at the top of the driveway is a common solution.

Key Design Decisions for Key Lots 😊

Home organization

Since there is no or very little street frontage curb appeal is of little concern, although you still want to create a 'wow' moment once the trip up the driveway is done.

The great thing about a key lot is that you will likely have more flexibility about how you place your home on the lot.  It doesn't have to conform with the 'square-on' set up of a home on a normal lot.

You can organise the foot print of your home in relation to your parking and yard space to take the best advantage of your key lot.

Think about the sun exposure and the setbacks on your lot (and the lots of the properties backing on to your lot) in order to find the best place for these spaces.

Building Considerations

Key lots can make like difficult for builders if the driveway access is too small for their heavy machinery.  If access is difficult, it will increase the cost or your build or remodel.

More about your site

Finding your site

Designing for your site

Site shapes