Post building near trees

[wesst]

I am ready to finally pull the trigger on an accessory structure at my home. Due to space constraints, the structure will be 20'x44' with a garage door at each end. Long story short, our lot is long and narrow, and covered with mature trees in excess of 40 ft tall. I love the trees, however every contractor has indicated trenching concrete footings around the parameter will most likely result in the trees dying. For this reason, I am thinking about going with post construction on an effort to save the trees since it blocks the neighbors.

I am looking for advice, as if I go the post construction, I will have to pour a concrete floor at a later date. If I do it all at the same time, the inspector has indicated a 42" trench footing must be poured with any concrete floor- even post construction.

I'm ok with taking out the trees, however I would rather give them a shot at living. If they die after the fact, I can have them removed either way, and yes I know if will cost more to have them removed once the structure is under them, but I'm just reaching out for opinions on what method you would go with.

Thanks in advance for your input!

 

[Stuart in MN]

Don't forget that the concrete floor will not be good for the trees either, assume it ends up covering up part of their root system. There are rules of thumb out there for how far away you need to stay from the base of a tree, I think it will depend on the species.

 

[lakeroadster]

One suggestion would be something along the lines of "Foundation System 2", shown in this link? https://www.lesterbuildings.com/Materials/Foundations/#Uni

That being said.. the tree roots may come back and bite you at a later date, by heaving the slab.

I am looking for advice, as if I go the post construction, I will have to pour a concrete floor at a later date. If I do it all at the same time, the inspector has indicated a 42" trench footing must be poured with any concrete floor- even post construction.

Ask the inspector if they will waive this requirement if you have drawings stamped and signed by a Professional Engineer. Usually they will... it's a liability thing for the county / city / jurisdiction.

 

[Warrenator]

Also, if the big old trees fall on your new building, you will slap your forehead and say bad words.

 

[matt_i]

How close to the trees are we talking here?

 

[tarmy]

Couple of things to consider...

Fire...they will burn...

Wind...they fall down...

Limbs...they drop pine cones, pitch, branches and bird poop...and squirrels will use them to get on roof and get into attic...

They grow...so need additional upkeep...

They will heave the slab or walls...

They will find water...under the slab...and foul up underground utilities...including electric conduit...

Other than that...go for it...

 

[wesst]

Trees are less that 5 feet from the proposed edge of the structure. That being said, the trees are fully mature pines. One is a beautiful birch, and five are pines.

 

[dfiler2]

You might want to visit the http://www.forestryforum.com/, lots of good people there that know trees and a bunch of them are from MI. There is a forum there called "Urban and Community Forestry", I'll bet you would get some good advice.

 

[EOC_Jason]

Trees are less that 5 feet from the proposed edge of the structure. That being said, the trees are fully mature pines. One is a beautiful birch, and five are pines.

Less than 5 feet? I would cut them down without even thinking about it...

Pines have a shallow roots that WILL go under your slab and jack it up. Any sewer line they will work their way into...

Pine needles & cones will pile up on your roof...

Like someone else said... Fire, Wind, Limbs, Growth, etc, etc...

It might look nice, but some point down the road they will become more of a headache than they are worth, and you will be saying to yourself, "Why didn't I cut these down before I put the building up?"

 

[cowboy73]

Cut the trees down now before they cause you problems. A good rule of thumb is that you shouldn't have any structure within 50' of a tree. That way the roots or the tree falling over shouldn't affect anything.

 

[n20junkie]

50', most lots in suburbia would be clear cut if we went by that rule.

It depends on the species, age and a bunch of other factors.

A tree that is only 5' from a structure is too close IMHO. First off, even things like scaffolding can be a real pain with that lack of clearance.

Is it 5' from the wall, or 5' from the overhang?

Trees grow, and with that the primary root ball grows. Being that close, it is almost a guarantee that the posts will get pushed and the floor may get picked up over time.

 

[CN Spots]

From what I've been told, the general rule is avoid the drip line. No soil removal, addition or cutting/digging or you endanger the tree. Soil compaction from heavy equipment traffic will harm them too. A trench 5 feet from the trunk sounds lethal to me. I loves trees too but I'd have to let those go. Maybe plant some smaller, ornamental trees in their place?

 

[bczygan]

Reconfigure your building plan.

 

[nmcqueen469]

If they were old, mature hardwoods, I'd move the building before cutting them down.

But in your scenario, I'd get rid of them, they are only pine trees. 5' is way too close to even consider leaving them and they are all but guaranteed to die after the construction.

 

[Falcon67]

I dunno - at work (university) we have a ton of mature trees, some surrounded by concrete on all sides. They are doing fine. There is what was a smaller Mesquite behind my shop. As part of the foundation I mutilated the hell out of the surface roots in the slab area. It's twice the size it was in 2011 and thinking I should have killed it when I had the chance. One of the large live oaks in my front yard is only 4' off the driveway, it's just fine thanks.

> A good rule of thumb is that you shouldn't have any structure within 50' of a tree.
What, that'd never fly in these parts. No way. There is a 60+' pecan next to our 3 story building, I could reach out the window on that end of the building and pick fruit.

In Houston there are many, many lob lolly and misc very tall pines located next to structures. Doesn't seem to bother them. I'd be more worried about pine beetles killing the pines, or one getting hit by lightening - they like to explode. Or they die in hours after the hit and become a brittle Sword of Damocles hanging over your structure.

 

[Leaflessshadetree]

If they were old, mature hardwoods, I'd move the building before cutting them down.

But in your scenario, I'd get rid of them, they are only pine trees. 5' is way too close to even consider leaving them and they are all but guaranteed to die after the construction.

If they were old, mature hardwoods I'd consider cutting them down and use the results to fund the project (and plant new trees).

 

[ptgarcia]

I'd remove the trees and plant new ones where they'll thrive without damaging your new building.

 

[rustyjames]

Been through this along time ago building a shop. I like trees but you will be dealing with these trees sooner or later, it's much easier doing it sooner.

 

[6768rogues]

You should try to avoid building or driving heavy equipment within the canopy diameter of the tree.

 

[wesst]

Thanks for the input. I will most likely cut the trees down. While I would like to relocate the building, I am very limited on space due to a narrow lot and required setbacks.

Again I appreciate the input, but wanted to see if anyone has experienced similar situations with success.

 

[keen]

I built mine post frame specifically because of the trees.

I've got 1 good sized oak behind my old shop that I had to intrude on - but stayed within or close to within guidelines for maximum root coverage, and forced the crew to not drive the bobcat or telehandler closer than the posts on that side (they had to work from the inside for some of that area).

I have 5 smaller oaks closer - two within 2 feet of another corner. There was some trimming (and 2 others came down) to fit.

One of those closer oaks I had to take down after construction - the first big storm caused it to move a -LOT- more than I expected and put a big ol' dent in the wall and roof. Had to get that fixed....

The slab IS thickened typically near the edge - at least down here in florida. my 4" slab is about 12-14" on the edges. But still better than a full depth foundation.

9 years in, and so far so good. (a lot of the not live oaks are having trouble, but not from the building. we've got a mistletoe overgrowth problem all over the area). I accept that the trees may not survive - but I figured I'd give them a chance and deal with what comes.

No slab heave so far - but I accept that it might happen. The old slab (under about 1/4 of the new slab, and the other half of it still exists) is 30+ years old with no heave. Even the chinaberry on one wall that is almost literally a part of the wall (leans on the edge of the roof on that side) hasn't made any slab movement.

But ymmv for different trees, of course.


3 years ago a new septic tank and field went in the back yard - the field was a full 4 foot trench 3 feet away from two oaks. One of those two had significant machine work on it's opposite side (that's where the machine had to sit to dig for the tank, and where the pump tank line heads to the field...). It rotted at the base and fell last year. The other (only 1 side dug up) is still hanging in there. Again, we accepted the risk (no structure risk with those, just a fence) instead of dropping the trees and leaving that part of the yard barren.

Mind you, we lost 15 trees in one year with 4 hurricanes and have lost another 10 or so since (lightening, flooding, disease) so maybe we are a bit tree-loss-averse......

 

[like2wheel]

From what I've been told, the general rule is avoid the drip line. No soil removal, addition or cutting/digging or you endanger the tree. Soil compaction from heavy equipment traffic will harm them too. A trench 5 feet from the trunk sounds lethal to me. I loves trees too but I'd have to let those go. Maybe plant some smaller, ornamental trees in their place?

OP didn't specify if the trunk is 5 feet from the proposed structure, or the tips of the branches.
That could conceivably put the structure outside the drip line.

 

[wesst]

Sorry, it is 5' from the trunk. I have attached a picture of the space. I would like to squeeze the structure between the birch tree and the row of pines. Basically I know the birch has to be removed, however the pines are what I questioned.

 

[TractorJeff]

My dad left those pines on a 42" foundation dig. He ended up taking them down one at a time because of the incredible amount of needles/cones they shed on his shingled roof. These were a magnet for Red Squirrels even though the building sat no where near a Forest. They turned out to be worse than Rats! Chewing on everything and leaving cone pieces all over inside the garage/shop.

 

[Falcon67]

X2 - big pine trees are pretty...in a national forest. In your yard, just a PITA.

 

[tarmy]

Couple of things to consider...

Fire...they will burn...

Wind...they fall down...

Limbs...they drop pine cones, pitch, branches and bird poop...and squirrels will use them to get on roof and get into attic...

They grow...so need additional upkeep...

They will heave the slab or walls...



They will find water...under the slab...and foul up underground utilities...including electric conduit...

Other than that...go for it...

I gave this list to you to think about for a reason...trust me when I say...learn from others experience...every single thing listed happened....