How to Size a Dog House
One of the most important attributes of a dog house is that it be the
appropriate size for your pet.
If the house is too small, it will be uncomfortable and your dog
won't want to stay in it. If the house is too large, it will be harder
for your dog to retain body heat in order to stay comfy and warm. Also,
dogs feel more secure in a snugfitting abode.
So, you ask: how do you determine the proper size for a dog house?
Well, there's more than one answer to that seemingly simple question,
depending on who you ask. The "standard" answer is that a dog house
should be large enough to allow the dog to stand up, turn around and lie
down comfortably inside the house. This guideline is supported by
The Humane Society of the United States as well as a number of other
animal organizations.
In researching this topic, I contacted the local animal control
center, several pet clinics, and a dog trainer at a pet boarding
facility. They all supported this guideline as well. You'll also find
quite a few web sites for veterinarians, humane societies, and dog house
vendors going with this "stand up, turn around and lie down comfortably"
guideline. That's why I refer to it as the standard guideline.
There's just one problem with this guideline: it assumes you can
physically test out the dog house with your dog. If you're buying a dog
house online, you're SOL (somewhat outta luck).
Dog House Sizing Formulas Galore
Fortunately, there are a number of sizing formulas for determining
the recommended dimensions of a dog house given the dimensions of your
pet. Unfortunately, because there is no single "golden rule" sizing
formula, you have to decide which formula or variation of a formula
works for you. As you'll see, the formulas are all similar but
different.
Some dog house vendors provide sizing formulas for their specific
products. In this situation (assuming you trust the vendor), it's a
simple matter to find a dog house that fits. If the vendor doesn't
provide decent sizing guidance or you're planning to build a dog house
from scratch, then your job is a little more involved.
So, without further ado, here is a roundup of the dog house sizing
formulas that I'm aware of:
Asheville
NC Humane Society  They offer plans for a dog house with an offset
doorway and a slanted single panel roof. Their sizing formula is:
Depth = dog's length + 12"
Width = dog's length + 18"
Height = dog's height + 3" (low side), height + 9" (high side)
Ontario Humane
Society  They offer rather detailed sizing recommendations for
Ontario's outdoor dogs:
Size of Sleeping Area Floor Space  With each inch of your dog's
height (measured from top of shoulder to ground) allow 36 square inches
of floor space. For example, a dog 12 inches tall needs 432 square
inches of floor space, or a floor area of 16" by 27" = 432 square
inches.
Height of Sleeping Area  Add 1 or 2 inches to your dog's measurement
when in a sitting position (from top of head to ground), in order to
determine the ceiling height. For example, a dog 12 inches tall will
have a sitting height of about 14 inches and the doghouse ceiling should
be 15 or 16 inches high.
Overall Doghouse Dimensions  For example, a Dalmatian (20" tall,
sitting height 23") doghouse should measure: sleeping area  20"x36";
hall area  12"x20"; ceiling height  25"; doorways  10" square; roof 
36"x72".
WOOD
Magazine, issue #80 (Aug 95)  The editors provide the following
rules of thumb for creating a Pooch Palace:
1. The depth should be 11/2 times the length of your dog.
2. The width should be 2/3 the length of your dog.
3. The height should measure 1 1/5 times your dog's height measured
from the ground to the top of the dog's head.
In case you're interested, this issue contains a plan for an
insulated dog house with an entry deck and an internal removable
divider.
Blythe
Wood Works ABC method  Blythe has developed a copyrighted formula
to assist customers of their western red cedar dog houses. With their
permission, the formula is given below:
A. The door opening height needs to be at least one inch taller than
the shoulder to chest measurement. Also, it is recommended that the
house be elevated off the ground by half of the "A" measurement.
B: The width and depth of the house should be at least the "B"
measurement (the distance from the dog's nose to its flank, excluding
tail).
C: The "C" measurement is utilized to determine the correct dog house
height at the peak. The minimal house height should be 1.25 x the "C"
measurement (the distance from the top of the dog's head to his toes).
Blythe provides an online calculator to simplify using their formula.
DogHouses.com  This online dog house vendor makes the general
recommendation that the dog house needs to be just big enough for the
dog to enter and become settled. Their specific sizing formula is:
1. The height of the door should be at least three fourths (3/4) of the
dog's shoulder to ground measurement. The door height does not need to
be as tall as the dog or larger either. The dog will lower its head when
entering the dog house.
2. The next measurement is from the dog's nose to its flank. The house
should be no shorter or no more than 30% longer than this measurement.
3. The last measurement should be the height of the dog from the top of
its head straight down to the ground. Keep its head high and flat. The
house should be no more than 45% taller than this height.
Merry Pet/Ware Mfg Formula  A number of online dog house vendors
featuring products from Merry Pet and Ware Manufacturing provide the
following sizing guidelines.
1. The door height should be at least 3/4 of your pet’s shoulder
height.
2. The length and width of the house should be at least equal to but
not more than 25 percent larger than the distance between the nose and
the base of the tail.
3. The height of the house should be at least 25 percent (but no more
than 50 percent) taller than the height from the top of the dog’s head
to his toes.
Drs. Foster & Smith's (PetEducation.com, Purina ONE)  These vets
suggest that with your dog lying down, you draw a rectangle around him
that is 3" larger on all sides (12" if the house is to be used for
whelping). This provides the width and depth of the house. For the
height, they suggest four to six inches taller than the dog's shoulders.
He will not mind lowering his head.
Summary
Are you confused yet? As promised above, these formulas are similar
but different (some more so than others.) Depending on which formula you
select, the length of the dog house should be somewhere between 1 to
11/2 times the dog's length, the width 2/3 to 11/4 times the dog's
length, the height 11/4 to 11/2 times the dog's height, and the
doorway about 3/4 the dog's shoulder height.
If I were to condense the essence of these formulas into plainspeak,
it would be something like:
The height of the doorway should be a little less than the dog's
shoulder height. The length and width of the house should be a little
more than the dog's length. The height should be slightly more than the
dog's standing height.
You can work out the exact scaling factors yourself  within the
bounds given above. If your winters are very cold, it would make sense
to keep the house as small as possible to help retain the dog's body
heat. If your winters are mild, a larger dog house would be acceptable.
One final tip: Before spending your hardearned money on a dog house,
make a cardboard mockup. Coax your dog inside and see if he can easily
turn around and lie down comfortably. Tweak the dimensions of the
mockup until he can do so.
