Layer house conversion: convert the high-rise house or build new?
With hen welfare legislation pending in Congress, individual egg producers may want to evaluate the suitability of existing housing for use with enriched colony systems.
A diamond may last forever, but chicken houses and cage systems don’t. The hen welfare legislation, currently supported in Congress by the United Egg Producers and the Humane Society of the United States, calls for a multi-year transition from traditional cages to enriched colony housing in the U.S. If the legislation is enacted, egg producers will gradually retire existing cages and replace them with enriched or enrichable enclosures. Producers will have to decide whether to place these new enclosures in existing buildings or construct new ones.
Converting a high-rise house
Other things being equal, it is easier to maintain low ammonia levels in the air and control pests in houses with manure belt systems than in high-rise or deep-pit houses. These advantages have led designers of enriched colonies to make manure belts part of all of their systems.
Most high-rise houses have a post and beam system to hold the cages and catwalks up over the pit. The posts and beams have to be removed in order to put in the enriched colony system, which is supported by the floor of the house. In addition to supporting the old cages and catwalks over the pit, the posts and beams added rigidity to the structure. According to builders contacted for this article, in a typical high-rise house, some kind bracing or structural support will need to be added before the posts and beams are removed.
Is your house the right shape?
Enriched colony enclosures are a little bit taller than a conventional cage because they have to provide room for roosts and for the hens to flap their wings. Placing manure belts under each enclosure also increases the amount of height in the building that each level of an enriched system requires when compared to cages in a high-rise house. The actual size and shape of enriched colonies will vary by manufacturer, so you need to know the specific dimensions of each system before you can figure out how many enclosures will fit in your existing house from a height and width standpoint. Since manure storage will not be under the cages in an enriched colony house, the “pit” area of a high-rise house is available for enriched colonies.
Many high rise houses are 600 feet long or longer. Manure belt systems are engineered for lengths of up to approximately 550 feet. The ventilation systems are designed to dry the manure prior to removal from the house by the belt. According to the system designers, extending the belts longer would put too much manure weight on the belt, and running the belts more frequently would not allow enough time to dry the manure. Because of the length restrictions of the manure belts, houses built for enriched colony systems will likely be somewhat wider than houses designed for conventional cages.
Some producers who decide to convert houses over 550 feet long to enriched colony housing may opt to use one end of the house for manure or equipment storage.
Calculating the cost
If you have determined that an enriched colony system will fit in your existing building in a manner that you are comfortable with, you need to consider all of the costs of retrofitting the building itself. Builders say that the first thing to consider is if the building will stand up by itself with the cages, posts and beams removed. If not, you need to get a price for what upgrades are needed in the structure to make it free-standing. The builders add that particular attention should be paid to any posts or poles that are in contact with the ground.
Enriched colony systems are supported by legs that rest on the floor of the building. The system will be up to 550 feet long, and it needs to be level. Builders say that you will probably need to pour a new concrete floor in order to provide a level base for the system, particularly in a deep pit house where the floor did not have to be level before.
The building material covering the interior walls of the building should be removed to expose the insulation and wall studs. Builders say that the amount of damage that rodents have caused can be significant. Damaged studs will need to be replaced, and the walls and ceiling of the building will need to be re-insulated. Then, new interior wall coverings will have to be installed.
The condition of the trusses and the entire roof system needs to be evaluated when considering house conversion. The trusses should be inspected to make sure they have proper bracing. The truss plates should be checked to make sure they haven’t become loose. Builders say that if there is evidence of deterioration, an engineer should be hired to design the repair. The roof should be checked for leaks, and if there are or have been leaks, then roof purlins should be checked. Roofing metal should also be checked to see if it needs to be replaced.
The ventilation system for the house will need to be redesigned. If the enriched colony system doesn’t run the entire length of the house, then this will have an impact on the design of the ventilation system. If this was a high-rise house, then the old access doors for the pit will need to be sealed off and insulated. You should consider upgrading to tunnel ventilation if your old house didn’t have it.
One builder said, “In many cases, the old house just needs to go.” Another builder said, “Sometimes there is not that much difference in remodeling versus building new, especially if the remodeled house can only hold six tiers and the new house can hold nine or 10 tiers of cages, or if so many repairs are required that the conversion expense is very near the cost of a new building.” Building new allows for the structure to be designed to fit the specific needs of the enriched colony systems and can allow for optimum utilization of space under roof.
Another builder did say that the relative ease of getting permits for a remodel versus permits for building new can sometimes favor remodeling. Given the fact that no two houses are exactly alike and that local permitting processes can have an impact, the decision of whether or not to convert an old house or build new may come down to the preference of the producer as much as to dollars and cents.