Chicken coops must provide shelter and protection for the birds. Coops must be big enough for the chickens to live comfortably by allowing them room to flap their wings, walk about, and build comfortable nests. Chicken coops must also be hygienic—featuring changeable flooring (like sawdust, woodchips or sand), ventilation and room for humans to clean. Chicken coops must also provide warmth through insulation, heat lamps, or extra bedding and nesting material.
The size of a chicken coop is largely determined by the number of birds a poultry keeper has. Poultry expert and author Jeremy Hobson says, “If you intend to keep your chickens intensively, a house measuring 1.5 m x 2 m (5 ft x 7 ft) should be sufficient for six hens; if a run is attached it will accommodate 12 birds. For these sorts of numbers, a combined house and run area of 5 sq m (6 sq yd) per bird is adequate, although much will depend on whether you are keeping bantams, light large fowl or any of the extremely heavy breeds as Croad Langshans or Brahmas.” 
For various reasons extra space separated from the main hen house is essential for maintaining a backyard flock. Common situations which require extra hen houses include when brooding hens need to be separated from egg-laying hens, when cockerels and roosters need to be separated from female chickens, for quarantining sick birds, training show birds for the exhibitor’s booth, separating new birds in order to gradually introduce them to the flock and pecking order.
Various types of chicken houses are offered by retailers, including hen houses, chicken coops, chicken arcs, and chicken runs. These types of chicken housing can be permanent or moveable.
Often chicken runs are attached to chicken coops. In times that weather or predators hinder chickens from roaming freely in open spaces, a run allows chickens to move about in a protected outdoor space. Poultry keeping expert Rod Ludlow advises poultry keepers to “factor in 3 to 6 square feet of run per bird, although more is always better.” 
Chicken coops must provide the basic protection and shelter with a floor, walls, a roof, doors, windows or vents.
All chicken coops provide a roost and nest boxes. Some chicken coops feature waterers and feeders within the chicken coops. Poultry keepers who feed by hand or feed outdoors may not allocate space for waterers or feeders within the chicken coop. Some chicken coops include ramps for the birds’ access to nests, the chicken coop itself, or a variety of other features within the chicken coop.
The roost is a bar within the chicken coop which is where chickens typically choose to sleep at night. Poultry keeping expert Rod Ludlow states that the roost “replicates the tree branch that your birds instinctively want to perch on at night.” He also suggest that poultry keepers “provide 12 inches of roost per bird, and place the roost bar as high off the ground as your coop design allows.” 
The roost bar is not recommend to sit above waterers and feeders or open top nests since there is a high frequency of roost droppings.
Chicken coops are typically made from wood boards, plywood, or particle board. Sometimes chicken coops are made from recycled materials, like ecologically friendly recycled plastics. The walls are usually made of thicker wood boards so as to facilitate insulation in all types of weather. The flooring of chicken coops most often features loose bedding that is made of wood shavings, wood chips, or sand. This helps in maintaining a hygienic environment for the birds. Roofs must be water-tight and wind-tight, therefore often coop roofs are made from sheet metal, PVC, or shingles. 
Chickens famously love to peck at their food all day long, so it’s perfectly acceptable to leave their food bowls topped up with commercial hen food. Some owners feed their hens in the morning and evening to prevent pest infestations. Keeping track of how much you feed your chickens will help you maximise egg production and reduce the incidence of obesity amongst your flock. Allow your chickens plenty of access to grassy pastures during the day and they’ll lay you eggs with golden yolks and substantial whites. If space is limited, set up a run for your hens so they can peck at insects and get extra nutrients. You can also make your own chicken food by mixing grains, seeds and fibre.
Where you place your coop is very important, as chickens are extremely vulnerable to environmental hazards. First and foremost, keep your coop in a partially shaded, dry spot – never leave it in direct sunlight. Hens love to peck at the ground, and so ideally the coop should be placed on grass or, if grass is unavailable, dirt. During the evening or whilst your pets are unsupervised, it is wise to place them in a coop with a concrete base, as this will prevent predators like foxes from digging under and into the coop (Good article here from MyPetWarehouse). You can also bury bricks or stone under the ground outside your coop to discourage predators from digging. Be sure any coop you construct or purchase has lockable doors and a foldable ramp for extra security.
To increase egg production, a chicken coop can discourage brooding behaviour. To discourage brooding behaviour extra space might be needed in order to separate a brooding hen from the egg-laying hens so as not to encourage brooding in the flock, or simply to get the hen in question to stop demonstrating brooding behaviour completely. When an egg-laying hen demonstrates brooding behaviour, she can be separated from the rest of the flock and placed in a hen house without a nest. This discourages the hen from sitting on a nest and therefore prevent her from brooding. Alternatively, the hen can be separated from the flock and placed in a hen house for brooding, so that the hen can continue brooding without encouraging other egg-laying hens to brood.
Chicken coops must feature space for hens to lay eggs. Most poultry keepers create one nest for every two or three hens. Poultry keeping expert Robert Ludlow recommends “each [nest] box should be a minimum of 12 x 12 inches, or larger is possible.”  Nests should be sheltered within the chicken coops for the comfort of egg-laying hens. Many poultry keepers create a door on the exterior which can facilitate easy access to eggs.
In order to create optimal laying conditions, many poultry keepers install electrical supply and electrical lights within chicken coops. Egg-laying hens usually require 12-14 hours of daylight to produce eggs.  When the days become shorter, poultry keepers often use artificial light to simulate optimal laying conditions.
When designing and conceptualizing a chicken coop, poultry keepers should keep in mind the tips and advice offered from the above resources. Then in order to understanding how to accurately build the chicken coop which has been conceptualizing, it is important to consult building and chicken coop experts.
Building a Chicken Coop is a e-book and website written by Bob Keene. The website features tips on building chicken coops, while the e-book includes designs on a chicken ark, mid-size hen house, and large pitched roof chicken coop with easy to build plans and instructions.
This book from the Dummies series offers all the basics on requirements, tips, and materials for buildling a chicken coop. The book also offers sample designs and buildling instructions. This comprehensive book presents rudimentary information for the ultimate chicken coop building beginner.
Coops And Cages™ chicken coops are extremely easy to assemble. Sent straight to your home packed flat, all of the available products require only basic tools for assembly. If you have struggled to construct your own coop from scratch or simply do not have access to the necessary materials, these coops are for you.
Build Eazy features a step-by-step design of a moderately sized chicken coop for 8 birds. Including detailed drafting plans, these instructions walk poultry keepers through the materials, layout, and step-by-step instructions on how to construct a chicken coop.
Backyard Chickens touts over 450 chicken coop designs coops submitted by other DIY poultry keepers. This site features community member-submitted designs on small coops, medium coops, large coops, and chicken tractors. The site also features designs on homemade incubators and chicken brooders for young hatchlings.
With two warehouses (Wetherill Park and Mount Druitt) MyChickenCoop provide the ultimate shopping destination for premium quality, affordable chicken coops, rabbit hutches and dog kennels. They take pride in offering customers top quality chicken houses at the lowest price, guaranteed.
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