Short answer
A consentable line is a boundary that neighboring owners have treated as the property line, and kept, for 21 years. Pennsylvania law can make that line binding, even on later owners, even if a survey shows the deed line somewhere else. An old fence is often the line people have treated as the boundary. Whether one exists on your lot is a question for a Pennsylvania real-estate attorney; this page isn't legal advice.
The idea in plain terms
Deeds describe lot lines with measurements. Real life marks them with fences, hedges, walls and the edge of the mowing. When the two disagree and both neighbors have lived by the fence for long enough, Pennsylvania law can treat the fence line as the agreed boundary. The period that matters is 21 years, the same span as general adverse possession, but the idea is different.
| Consentable line | Adverse possession | |
|---|---|---|
| Core idea | Both owners recognized and kept a line as the boundary | One party used the other's land without permission |
| Time | 21 years | 21 years; 10 years for some small single-family lots (42 Pa.C.S. § 5527.1) |
| Typical evidence | A fence or other marker both sides lived by | Mowing, building or fencing the land as one's own |
Plain-language summary of FindLaw, Nolo and Timoney Knox; not legal advice.
Why it comes up so often around here
Much of this area was built a long time ago. Lansdale was incorporated in 1872 and Jenkintown in 1874. The Wyncote Historic District, listed in 1986, has 178 contributing buildings, many from the Queen Anne and Colonial Revival eras. Elkins Park's close-set Tudor and Dutch Colonial houses sit on lots laid out generations ago. On lots like these, a fence, iron railing or hedge can easily be older than everyone who lives on either side of it.
The question usually surfaces when someone replaces that old fence. A new survey shows the deed line a foot or two from the old posts, and one neighbor wants the new fence on the deed line while the other expects it where the old one stood.
What to do before replacing an old line fence
- Get the line surveyed if you plan to build near it. Abington, for one, wants evidence of a boundary survey for any fence within 5 ft of a line.
- Compare the survey to the old fence. If they match, the question goes away.
- If they don't match, talk to your neighbor before anyone pulls posts. Write down how long the old fence has been there and how each side has used the ground.
- See a real-estate attorney before you move the line in either direction. A written boundary agreement may be part of the answer, and the attorney can tell you whether to record it.
What we do when the old fence and the survey disagree
We set fences where the owner and the permit drawing say, and the drawing comes from the survey or plot plan. If we find old posts well off the surveyed line, we point it out before the job, not after. Several local codes push new fences off the line anyway: Montgomery Township wants boundary fences at least 2 in inside the owner's side, and Worcester requires a 6-ft fence to sit 3 ft in. Those setbacks also make it clear whose fence it is.
If you're replacing a fence that's older than your deed, bring whatever paperwork you have to the free estimate and we'll walk the line with you.
Common questions
Does a hedge or stone wall count the same as a fence?
Any marker both neighbors treated as the boundary can matter. An attorney can tell you how the facts fit.
If I bought my house 5 years ago, does the previous owner's time count?
That is one of the first things an attorney will ask about. Bring your deed and anything you know about when the fence went up and who built it.
Can my neighbor and I just agree on the line now?
Yes, neighbors can agree in writing. An attorney should draft it so it works for future owners too.