charles and ben prowell woodworks arbors

The Ups and Downs of Electronic Access with Wood Gates
prowell woodworks



Prowell Woodworks does not warranty any gate for eventual repairs that are the result of 'strike-plate actuated' electronic access hardware or the use of standard residential locksets.


Such hardware requires a swing clearance of 1/4" or less. This is the standard clearance for residential doors utilizing residential locksets. Unlike a front residential door which is insulated on one side and further protected by jambs and headers and a roofline, the gates are fully exposed to the elements on 360 degrees to a combination of rain, sleet, snow, sunlight, heat, dew and the relative humidity of the air itself. All of this absorbed and released from the wood as a living environment, resulting in a gate width that changes and will continue to change, or breath, for the 50 years or so it adorns your property.

If you are in, say, South Carolina or Hawaii or the Caribbean, with excessive humidity and heat interspersed with afternoon rains, the gates will breath more heavily. Therefore the risks of swelling beyond a narrow 1/4" swing gap to bounce off the posts is much higher. If you are in San Francisco, with its even temperate climate, the risks are reduced simply because the gate is not reacting to excessive shifts in weather.

When a gate has only 1/4" clearance, it runs the risk of expanding to wedge against it's post or jamb and require yanking and shoving to open. The repeated yanking and shoving over the course of weeks or months is not good for the joinery. The gate in many cases will continue to expand to where it simply bounces off the jamb or post. This results in the potential damage due to the wind catching it and slamming it repeatedly to bounce off the jamb or post for the duration of the wet season, which again is not good for the joinery.

The percentage of those gates with 1/4" clearance resulting in the above scenario is about 20%, which is far too high a risk if you are in the gate business. We are not willing to replace 20% of all gates we build simply to accommodate a request for 'strike-plate actuated' electronic access or the aesthetic preference of a standard residential lockset.

If you prefer to move forward, we will build your gate, but we will not be liable for damage due to the above issues. In other words, we will repair or replace your gate, but not for free. This is a contingent appearing several places on the web site, such as the Payment Page, as well as the statement requiring an approval sign-off.

A thorough explanation becomes complicated, and for those of you who are interested, the remainder of this page will address the issue on a more technical level.

STANDARD LOCKSETS: You'll notice that the latch bolt below has a beveled edge. This interacts with the strike plate and as the door closes, the beveled edge of the bolt withdraws into the lock cylinder with a spring action. Once the bevel bolt reaches the center of the strike plate (the hole in the center of the plate), the spring releases and the bolt is fully engaged into the center of the strike plate. Because the bevel is on only one side of the bolt, it cannot be pushed open without turning the lock handle that withdraws the beveled latch bolt back into the lock cylinder in the door. To open the door, you must turn the lock handle.

The latch bolt is a standard diameter, simply because all doors are standard thicknesses from 1-3/8" thick for interior doors to 1-3/4" thick for entry doors. The diameter of the latch bolt dictates the angle of the bevel, which in turn dictates the actual length of the bevel that comes into contact with the strike plate. By the nature of this, virtually all of your interior and residential entry doors are relegated to a gap of approximately a nickel's thickness. You might now go have a look at all the doors in your house to verify this. Bearing in mind that these doors are not gates. The residential entry door is insulated on one side and protected by a jamb and header, as well as a roofline. The interior doors are 100% insulated from the elements.

  Below is the image of a standard residential lockset.   A typical Latch bolt shown with it's strike plate that mounts to the door jamb.

THE 'STRIKEPLATE ACCUATED'' ELETRONIC RELEASE LATCH: These are mounted to either 1) the post / jamb, or 2) the gate itself.
1) When mounted to the post or jamb, they are mortised in flush and wired down the length of the post to a junction box connecting it to the power source and most commonly, a keypad release. The lockset used on the gate is a standard residential style, with the beveled spring-load cylinder that is set to a locked position. Upon activating the release by entering the proper code or being buzzed in from the house, the strike plate bar mounted to the post is released and the beveled cylinder can be pushed through the strike as the gate swings open.

2) When mounted to the gate itself, they are also mortised in flush to the edge of the gate at whatever height location is desired. In this application, there will be a rigid steel bar that that is mounted to the post or jamb that engages the strikeplate. When the strike is released, the strike passes the fixed bar to enable the swing. The wiring, however, must be channeled invisibly within the gate such that it feeds through dadoes in the gate's vertical latch stile, along the length of the horizontal rail, through the hinge stile, and out the other edge of the gate near one of the hinge placements. There is extra play left in the wire to accommodate the full open gate swing before being fed into the hinge post / jamb, and dadoed down the length of that jamb to junction with the power source at the grade.

Because the length of the steel bar mounted to the jamb or post is negotiable, the proper 3/8" swing clearance can be accommodated. Any handle or grip becomes a non-functional dummy. (The only disadvantage is the added cost of us embedding the wiring within the gate from the strikeplate to exit along the hinge edge of the gate. )

  Below, a typical electronic strike plate, made by Rofu or HES. Mounting to the post or jamb.   The bevel bolt above collapses over the rear wall and into the cavity. Upon entry, with the lockset in a locked position and the handle unable to turn, the non-beveled edge of the bolt passed away only when the rear wall is electronically engaged and released.


MAGNETIC LATCH: Although this is the only system that allows for the expansion and contraction of the breathing wood, it is also somewhat complicated to install on site, and somewhat cumbersome visually. A plate is mortised into the latch stile of the gate that contacts the wired corresponding box mounted to the post, making a connection that comprises a 300lb rating. As the gate swells and shrinks with the seasons, the plate simply slides across the magnet, allowing for the full 1/2" swing gap we recommend.

Magnal locks are built on the premise of an electromagnetic field.

>>To Securitron Web Site MagnaLock M62

  The box itself mounts to the post or jamb. The wiring, like the Rofu above, is fed down the post concealed, or by exposed conduit.   A diagram illustrating the principle of how the Magnal Lok works. The box is mounted on the post to the left. Onto the gate is mounted a Z-Bar, or large aluminum plate that when the gate closes, engages the magnetic field of the wired box. As the wood gate swells and shrinks, the Z-Bar slides back and forth on the wired box but the magnetic field remains engaged.

A crude mock-up of how it appears. The board marked Fixed represents the post, with the wired magnetic box. On the left, the typical Z-Bar mounted to what would be the gate. A large cumbersome piece of hardware, shown to scale by the black pencil in the foreground.

  Below, showing a Magnal 34R where the wired box is mounted to the post as a right-angle protrusion near the bottom, and the receiving plate is mortised into the gate itself, as shown below. The problem with this set up is that when approaching the gate where there is only a handle grip and not a working latch, people tend to push open the gate unaware it is locked into position with the magnetic hold. They push, are met with resistance, and push again, and with each push the upper portion of the gate moves in, or open, while the lower portion, held in place by the Magnal lock, remains connected. Eventually this becomes abusive to the gate's joinery.   For double gates, the wired box must be mounted to the inoperable gate, which is fixed in place with the use of a cane bolt. The hold of the magnetic contact is only as secure as the cane bolt, which by design is mounted at the bottom of the fixed gate and allows a fair amount of play to the rest of the gate.

Below, showing a Magnal 34R on site. The unit itself is housed in a metal box and welded to a steel post near the bottom of the gate. Making contact with the plate that has been mortised into the gate as shown in the above left photo. The plate is 1/8" proud of the face of the gate.

For gates that swing out toward the street, such as the image below viewed from within the property, the magnal unit is not exposed upon entry from the street. A good thing. If, however, the gate upon approach from the street happens to open in, toward the property, then the Magnal unit is mounted on the street side.





Mechanical Locks are different in that they operate on a mechanical release that is not dependent on electricity or batteries or even a wireless system.
The Lockey Mechanical Dead Bolt is probably the most reliable solution to those seeking security without a keyed dead bolt. Because the bolt itself is 1" long, it also allows for the swelling and contraction of the gate. You simply enter your code and turn the knob to release the bolt. It is often accompanied with a dedicated gate latch for those instances when there is, say, a social gathering with people arriving in streams. To prevent the need for everyone to enter a code, the code is overridden and the gate swings open freely, which can result in a slamming gate if there is wind. So the latch comes into play to insure the gate can be closed and latched, but opened freely by each arriving guest.

The product retails for $108-140.
You can source this yourself and manage the boring prep, or you can have Prowell source it and bore for $280.00


The Lockey M2210 is a marine-grade metal with a bronze patina.
Left-View upon entry

>>To Lockey Site


Right: View on property side.



ARMATURE MOTORS: These are designed more for driveway gates where one end of a motorized cylinder mounts to the post and the other end mounts to the bottom horizontal rail of the gate. It is wired to a junction box at the grade as well as to a keypad mounted to the post or column. When activated, they automatically open the gate at a steady rate, and close the gate at a steady rate, requiring no latch of lockset. They are effective but cumbersome. A fairly bulky piece of hardware costing about $1000 that for gates opening in toward the residence, are not visible from the street. For gates opening out toward the street, the motor is exposed and visible upon approach.

  Below is a typical armature DoorKing 6003 automated motor that mounts on one end to the post, and the other end to the bottom rail of the gate. 32" length.  

Below, a driveway gate showing the Apollo 1500 series armature closer.
(This particular gate has an overall opening of 12' or less and thus requires no steel frame)




The principles of a flush-joined wood gate.

Wood comes to us from the forests of British Columbia, spec'd for a minimum number of growth rings that insures the harvest is fully matured. We cannot buy wood from the American northwest simply because it is harvested far too early. From BC, the logs are shipped to the mill of our choice in Washington state, and from the mill they are shipped to our shop in northern California as dimensioned lumber that is clear, vertical-grained, and kiln-dried to about 7% moisture. All three regions--BC, Washington, and N. California--share more or less a similar climate. Lots of rain, temperate humidity, and mild summers.

Once it leaves the shop, as an assembled product, and embarks on what's often a cross-country transit to a climate wholly different from its genetic DNA over the past several millennium, it experiences for the first time, once installed, the full 360-degree exposure to a climate of severe winters, or humid summers where the air is thick as Jello.

The result, for several weeks, is the wood breathing heavily. The way someone from San Francisco might do if visiting Mississippi in August. The wood acclimates and adjusts, gasping and panting in a sequence of expansion and contraction that goes on for several weeks until eventually stabilizing and settling into a pattern of minimal breathing that will last for the next several decades.

It's those first several weeks that present a problem for all those preferring an electronic access for their gates.

Wood breathes perpendicular to the grain. As it takes on rain or dew or humidity, it swells. As it experiences dry heat, it shrinks. The two vertical frame pieces of the gate are called Stiles. These breath horizontally. So if they arrive at 5-1/4" width, they will, depending on the regional climate, potentially expand to 5-3/4" width. But because they arrive at only 7% moisture, they will seldom contract, or shrink, more than 1/4".

Why is kiln-dried 7% moisture preferred? If we worked with green wet wood that had been logged the week before and was still wet with the plasma of living cells, our tight joints would open up as the wood dried and shrank the way firewood must dry before being burned. For assemblies relying on woodworking joinery instead of fasteners, it is essential that the joints are cut and fashioned with a relative moisture between 7-9%. (less than this and the cell structure of the wood fiber itself breaks down, hence why you see very little in the way of exposed wood assemblies in places like Phoenix or Las Vegas).

Now that we understand the properties of the wood, let's consider the variables of where it goes once leaving the shop in northern California. If the gate is delivered to somewhere within the San Francisco Bay Area, there will be minimal acclimation, as the entire Bay Area shares a similar temperate climate. If a gate is shipped to Memphis, or basically anywhere with seasons and relative humidity, it takes on the moisture of that humidity and swells, or expands to a larger width (Remember, the Stiles are what swell and they swell horizontally). If we finish a gate in, say, January, and ship it east, the dimensional change is minimal simply because cold and snow tend to contract the wood. If we build a gate in July and ship it east into the high humidity of summer climate, the gate swells. The more heat and humidity at the end destination, the more initial swelling. And because just about everywhere east of the Pacific coastal range experiences normal winters and summers with rain and humidity, this phenomenon is exempt only within those areas along the Pacific coast. A narrow corridor where the weather is unlike anywhere else in the country. (A good reason why it is also an area of high housing costs).

The properties of a typical electronic locking system only engage with a swing clearance (the gap between the gate and the post) of 1/4" or less. Imagine your front door, or any door within your house. Look at the gap between the edge of the door on the lock side, and the jamb and you will see the approximate thickness of a nickel. That's because the same type of lockset is most often used on gates with electronic releases. And because the nature of the cylinder set within the edge of the gate, or door, has a spring-loaded beveled edge that engages the strike plate, the 1/4" gap cannot be more or the bevel will simply not engage at all. If that cylinder were longer, and the gate swelled, it would be the shaft of the cylinder itself, and not the bevel, that bounces off the strike plate. So the nature of standard lock-sets do not work, by physical design, with a swing gap of anything more than 1/4".

But 1/4" is too little to accommodate the acclimating expansion of our gates. The gates, upon arriving and being installed and absorbing the changes in varying climate regions once fully exposed, naturally begin to swell once they experience their first season with humidity. (So if the gate is installed between late October and early March, everything will be fine until the heat and summer rains and daily humidity of the warmer season arrives).

The gate swells and quickly it swells beyond the 1/4" gap of your electronic lockset and it continues to swell until it becomes wedged tight against your gate post. The electronic lock is instantly disabled and at this juncture the gate must be shoved and pushed and yanked simply to gain access. A horrible set of parameters for the gate. And because the gate will not latch or close, it often is left to slam and bang against the post with each thrust of wind. And eventually something gives. First your patience followed by a temper tantrum followed by a string of cursing expletives directed toward Prowell Woodworks. Followed by the gate finally giving in to the abuse and manhandling and our homeowners calling demanding a new replacement gate.

The above scenario occurs about 20% of the time with any gate shipped anywhere with a swing clearance of anything less than the preferred 3/8" swing gap.

So you will see others with electronic access system that seem to work just fine. Perhaps even your neighbor's gate. But if you are in the gate building business, a 20% recall rate is about 19.999% higher than what is acceptable.

Therefore, any gate subsequently utilizing a standard door lock or electronic access loses it's warranty the moment it leaves our shop. We will not replace such a gate. There is no way to hide the evidence of such a lockset. You gambled, and the price for those whose imperatives are electronic security, the next option is wrought iron, preceded by a round of cursing expletives directed toward Prowell Woodworks.



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