Fence Buyers Guide
Market Guide for Purchasing a Fence
A good contract will cover most aspects of an installation. Important details to look for are: A description of the work to be performed, responsible party for different aspects of the job, work schedule, warranty information, work authorization (permit) information, proof of insurance, payment terms, structural settling and concealed conditions clause, and proof that the Contractor is licensed by the Contractors’ State License Board.
Your contractor must be licensed, bonded and insured, and have compensation insurance for his employees. A contractor can easily supply you with proof of all the above, so don’t hesitate to ask. You will usually get two out of three of the following qualities in a contractor: price, quality, and timeliness.
Start with a reputable, well-known firm. Obtain a bid that is all-inclusive and then have other contractors bid on the same items. Compare “apples to apples”. This is a good way of leveling the playing field. The lowest bid is not always the best bid.
The Complete Job
Job site safety, Fence drawing, site plan, soil stability, posts, footings, grading, Fence, electrical and communication supply, entry system, fire medical emergency lock, Fence configuration, Fence operator, system power and communication lines, exit loop, safety loops, photo electric eyes and other safety equipment, lighting, site cleanup and restoration. All these items will be discussed in the following paragraphs.
Job Site Safety
The job site has to be safe. All excavated areas need to have cones or barriers. Protruding reinforcing bars, “rebar”, need to be plastic-capped. All garbage has to be cleared away and all dangerous areas cordoned off.
The purpose of a drawing is to see the fence as it would appear when finished. It should include any posts, columns, and lighting. It is also good to see the side-to-side slope of the road, as it would appear under the fence. This is especially important if you have a lot of slope. The width of the road should also be included. A fence drawing is usually required when obtaining a permit.
The site plan is important for showing the location of both the fence and operating equipment. A good plan will show where all the wiring is buried and is useful for future repairs and any excavating you may want to do later. A site plan is usually required when obtaining a permit.
If the soil is not stable there is a good chance your fence will sag. Soil conditions are the first thing to look at before you begin your project. If soil is not solid or has high clay content you will need additional structural support. You may need a grade beam or outriggers. Grade beams are concrete beams that connect posts or columns together below grade. Outriggers are metal arms that extend out in the two directions the fence swings and are anchored in concrete. Post-holes have to be square or the swinging motion of the fence will eventually enlarge the holes and your fence will sag.
Footings for Columns
Concrete footings are required if you plan on installing columns. The column footing needs to be installed at the time of the fence installation. Footing size is determined by column size and soil condition. The footing should be at least 18” deep and be at least six inches wider than the proposed column on all sides. The footing should have a rebar cage with vertical rebar for the column. It is always advisable to connect footings together with a grade beam.
Underground Service Alert
Make sure that either the contractor or you call for an underground utilities check before excavating. In most areas this removes liability if the contractor should cut through a buried utility line. The various utilities come to your job site and mark all underground utilities, usually at no cost.
Fence posts support the weight of the fence. The posts can either be decorative (flank the fence), or be embedded inside the masonry columns. Embedded posts are set in the middle of the column footing and are used to hold the hinges, equipment vaults, lighting, and other accessories. Fence posts should be at least 5 inches x 5 inches and set 36 inches below grade. The minimum width of the hole should be 24 inches x 24 inches and be filled with a rebar cage and concrete. The holes should be square to prevent loosening by the Fence’s swinging action.
Some sites are flat. Those that are not may need grading. Water flow should be considered when grading. All added road base has to be compacted.
Heavier fences have a tendency to last longer. If hollow tubing is used it should be of a heavy gauge. The frame should be of at least 1/8 inch wall thickness and stakes should be at least 1/16 inch thick. The fence must have weep holes to allow trapped moisture to vent or the fence will rust from the inside. All weld slag must be removed before painting or powder coating. Removing slag is a tedious process. If not done thoroughly, it will severely limit the longevity of a fence. Since paint does not get into all the tiny spaces surrounding the slag, it later falls off leaving a bare spot where rust begins. You can tell good workmanship by how smooth the finish feels when you run your hand over it. Check the areas around welds, and check several fences built by your prospective contractor for this quality.
The most common fence material is iron (or steel), but aluminum is becoming increasingly more popular. Sculptural fences can also integrate unique materials into the design of your fence, such as wood, glass, or exotic metals.
Steel fences provide a stronger “feel” for your entryway and are less prone to damage if impacted. With currently available coating technologies, such as galvanizing and powder coating, decay due to rust is virtually eliminated. In addition, more embellishment choices are available in steel.
Fences can also be fabricated from aluminum. The advantages of aluminum are corrosion resistance and lighter weight. Corrosion resistance makes aluminum an attractive choice for fences that will be located in harsh environments. Lighter weight means that less rigorous structural support will be required for the installation. Aluminum can also be powder coated, so a wide variety of colors are available.
Wood, glass, and exotic metals provide a beautiful presentation for your fence, but they should be integrated into a steel frame to support their weight. In most cases the fence is fabricated so that the unique material is easy to replace.
Powder coated finishes are superior to enamel and can last up to 15 years. A good enamel paint job will last up to 6 years. Single coat paint jobs, also called primer paints, last only 2 years at best and should be avoided. Galvanization should be considered if you live near salt water. You may powder coat over galvanization if you prefer a different color.
Electrical and Communication Lines
The National Electrical Code calls for electrical lines to be buried at least 18 inches underground. Unfortunately we often find these more shallowly placed. It is not a pleasant experience if you hit a power line. Even if you don’t get shocked you will endure a costly underground splice.
Power and communication lines must be in separate conduits, for safety and to prevent noise on your telephone or intercom system. The conduit should be larger than necessary for easy wire pulls and future repair. The wire should be large enough to deliver the needed current after line loss. Line loss is a voltage drop that happens whenever power is delivered over long runs. Almost all underground conduits fill up with water. Use wire with appropriate insulation to hold up to these adverse conditions.
Most single fences (one operator or motor) need 10 amps at 110 volts AC. Consult an electrician before laying long runs underground so that you get the right gauge of wire. Splice or “Christy” boxes, should be installed at least every 200-300 feet. Use high quality communication wire, preferably direct burial cable installed in conduit.
There are many entry systems on the market, many of which are good, though some are more difficult to program than others. Check with your installer on ease of programming. Determine whether you need a simple keypad or one that communicates through your telephone system. There is a large cost difference between the two. Card reader units are used more in industrial applications and multiple dwelling communities. Make sure the “goose neck” or pedestal mount is sturdy. The unit should not move when you use the keypad. In certain applications wireless intercom systems can be installed. These units either connect to your phone system or require a separate base station for direct communication and Fence operation.
Video cameras can be installed in your telephone entry device and around your entryway. Video surveillance systems can range from a single camera and display screen to a system that monitors your entire property. Contact your installer to determine the system that is right for you.
Fire / Medical Emergency Lock
Most municipalities require you to have a fire / medical lock to allow emergency crews to enter your property without damaging your Fence or automation equipment. Make sure this item is not left out of your installation; you will only have to install it later.
In addition to standard slide and swing fences, other proven options are available to help you overcome difficult terrain conditions or space constraints. Uphill hinge: The uphill hinge mechanism causes the far end of the fence to rise as it opens (to clear the upslope). The hinge end of the fence will coincidentally be directed towards the center of the driveway (decreasing entryway width). Lift fences: The vertical lift fence rotates 90 degrees, vertically, to open. The fence can be opened or closed by hand in the event of a malfunction. The fence operator is rather large since it includes the counterweight. Cantilever fences: The cantilever fence is a slide fence that is suspended in space, so no driveway track is required. Cantilever fences are longer than traditional slide fences because of the counterweight member.
There are several ways to operate a fence. Swing fences can use four types of operators. A swing arm operator, which is a box, that sits off to the side and has an arm extending to the fence. A ram arm is located on the fence and post and uses either a hydraulic piston or a jackscrew-operated piston. A column mount operator mounts on a wall or column to open the fence with a swing arm style action. Underground operators are located by the hinge and operate the fence from below grade.
The simplest to service and install is the swing arm operator. The advantage of the ram is that it is smaller and takes up less space. The column mount operator uses less space that a traditional swing and does not require a niche in the column to operate. The underground operator is the most expensive but is very attractive in that you see no equipment. The swing arm is usually the fastest of the operators. The swing arm units also handles a Fence very smoothly and slows down toward the end of each cycle. Some ram arms do not have a slow down feature and the fences have a tendency to shudder at the end of each cycle. This shuddering is more pronounced when the fence is longer as in a single swing fence installation.
Slide fence operators are commonly installed at the end of the fence in the closed position but can also be installed at the end of the fence in the open position. In the first configuration a chain is attached from one end of the fence to the other (near the bottom) and passes through the operator, which shuttles it back and forth. In the second configuration you do not see the chain or any operating equipment near the fence. Sliding fences are more hazardous than swing fences and should be equipped with appropriate safety devices.
Either type of fence operator is available in 110 volt AC or low voltage DC. The DC powered fences can run off low voltage transformer or solar panels. Solar installation requires more maintenance than an AC powered system. Quality operating equipment will generally last 12 to 20 years before it needs to be replaced. Most installations use a built-in timer that closes the fence after a set period of time
An exit loop is wire that is either buried beneath the driveway or cut into the concrete or asphalt. It is located behind the fence. Locating it far from the fence is best. A vehicle triggers the loop, which acts like a big metal detector and opens the fence, allowing the vehicle to exit.
Loops can be a weak spot in many fence systems. All loop connections must be soldered and any underground connections completely waterproofed in order to avoid problems. The size, shape, and number of turns of wire in the loop will determine the sensitivity. Loops cut into asphalt or concrete should be 1″ or more deep. Those buried in earth or gravel should be 4-6 inches.
Reversing Loops, Edge Sensor Switches, and Photo Eyes
Reversing (Safety) loops are buried or cut in the pavement in front of and behind a fence. They prevent the fence from closing on a vehicle in its path should it stay there past the “momentary open” timer setting.
Edge sensor are long strip switches as found on elevator doors They are used halt fence motion if an obstruction is encountered.
Photoelectric “eye” and safety loops are often used in conjunction with one another. A single photo eye may be used on a slide fence to hold the fence open in case a vehicle stays too long in its path or reverse if a vehicle enters its path as it is closing. Other “entrapment zones” created by the fence (e.g., sliding behind a fence or wall) should be protected by safety devices well.
Finally, all fences should be equipped with a warning sign, visible from both sides, to prevent accidents and limit your liability. For more information refer to our section on regulation U.L. 325 safety guidelines.
Personal Safety & Underwriters Laboratories Standard UL-325
By definition, automated fence systems are intended solely for vehicular traffic. However, personal safety is paramount to any automated fence system. For that reason, Underwriters Laboratory developed UL-325, a voluntary standard whose primary intent is to prevent entrapment or injury of people by automated fence systems. UL-325 is not concerned about the Fence contacting vehicles, only the entrapment or injury of people.
Compliance with UL-325 means that you have a separate walk through fence installed for pedestrian traffic, have sensors and guards installed to protect people from entrapment areas and pinch points, have slide fences constructed so that a 2-1/4” diameter sphere cannot pass through critical areas of the fence (and associated fencing), have operational controls located at least 6’ from the fence, and have any other safety measures installed that are deemed necessary for the specific application. You should understand that automated fences are not intended for pedestrian traffic and notify the Contractor if you choose to have UL-325 safety features installed.
Lighting often is located either on top of fence posts or on top or on the front of columns. The best way to control lighting is with a combination timer-photocell. The timer is set to activate in the afternoon and has a photocell located between it and the lights. Once the timer is activated, the photocell prevents the lights from coming on until dusk. The timer shuts off the lights at a predetermined time, (e.g., midnight). In this way the lighting tracks the seasons and you do not have to keep adjusting the timer.
A project is not finished until the job site is thoroughly cleaned and restored to its former state. Special circumstances should be discussed (e.g., hauling away certain debris). It should be made clear whose responsibility this is. The contractor should always perform ordinary clean up at the end of each day.
Sculptural fences installs complete fenced entryway systems using the finest materials and methods. We work closely with you to determine the best system for you, based on style, functionality, and cost. Contact us to arrange for a no cost site evaluation and cost estimate.