What you are asking for is legal advice. Need to talk to people qualified to give it, maybe one or two candidates have been mentioned in your description.

Sadly, it seems you're closing the barn door after the mule escaped and was hit on the highway, and you're trying to hold the driver of the truck responsible. I'm not a lawyer, but I don't hold much hope of you getting any satisfaction in resolving this situation.

Preservation of existing trees when building on a 'wooded lot' can be a daunting task just by virtue of the process, and unfortunately, it's one that typically rests fully on the shoulders of the homeowner. You hired a builder - he and his crew build. In most instances, they have no clue about root compaction, piling dirt and building material over roots, etc. They figure if they don't knock the trees down, they'll be fine - but as you're finding, that's not necessarily the case.

Check out some of the articles in the Google search below to see what should have been done during the construction process. There may also be some recommendations on things you might be able to do to help some of the struggling trees survive.
Good luck.

Here is a link that might be useful: Preserving existing trees during home construction

At the very least it seems the builder should be the one to pay to have the trees taken down. My builder gave us a one year guarantee and came out to remove any trees that were dead after one year (fortunately there were none, but he did have the tops of two tall trees removed because the tops had died out - those trees did very well in the years afterwards).

Before taking any action or writing a demand letter, you need to consult with an attorney who has expertise in civil litigation.

The legal question goes to damages - what would your house be worth with the trees v. without the trees. How were you damaged by the builder's actions? What is the case law in your area about damage to trees by builders?

As you say, you don't have much evidence except your neighbor's recollections so it becomes one person's word against another's. You don't have contemporaneous evidence that you expressed concerns at the time - photographs, notes or letters written while construction was ongoing.

You may have a stronger case than your post implies. A consultation with an attorney who has expertise in civil litigation probably won't cost much and will set your mind at ease about whether you should go forward or put the issue to bed.

Litigation is emotionally consuming. After you get legal advice, you need to decide if you want to pursue it. You can also check with your local bar association. In some jurisdictions, people take issues like this to mediation.

An professional witness won't be cheap, but about the only avenue to win such a case unless you had an air-tight building contract with very explicit specifications about tree conservation. I'd recommend an ASCA (American Society of Consulting Arborists) or a Master Certified ISA Arborist.

Unfortunately, that kind of constractual protection needs to be done before the architect decides where to place the buildings and put all of the hard surfaces. Certainly before the builder brings his crews on the property. Protection specs need to be on every single copy of the blueprints.

Unless these trees were well away from any construction activity, which can be devastating to established trees, I'd wager that the stock piling of the soil was insult added to injury. Heart-breaking, I know.

I've never met an architect or builder that knew anything about tree physiology and what needs to be done to truly protect them during the construction process. I've only met a handful of landscape architects with that kind of knowledge.

I sure do wish you luck if you decide to pursue this legally.

Here is a link that might be useful: Click here for information about ASCA

Damage done to trees by construction takes place for years after the initial injury. A one year warranty is nearly worthless in such cases.

+oM