How low of an earthquake does the USGS report?

I've been in a few houses where someone walking in the next room made the house shake.

FWIW my grandmothers' picture of The Last Supper was crooked for 35 years.

The same thing happened again yesterday at 15:29. Again, neighbor wasn't home. There was no heavy traffic nearby. No large aircraft overhead. Nothing external that could explain this. My son was home and he noticed it before I did. I checked the PNSN Recent Events page for Earthquakes and it again showed nothing.

When they built this place they had a drainage pond underneath this unit. That was filled in. How does that affect the settling? Can it result in some sort of sink hole?

Krispy, what state/county/city are you in?

I know something about sinkholes here in MO but if you are in CA or somewhere else, I hesitate to advise you on sinkholes. In general, sinkholes are related to karstic rock, i.e. erodable limestone that forms caves. I have no idea what conditions you have out there. Normal settling would not make your house visibly move. I could believe that an underground cave collapsing could create local rumbles above, but there aren't caves just everywhere.

I would suggest getting in touch with city or county offices that might be able to help - start with building inspection for example. Not that you need a building inspection, but perhaps they can advise you on other resources to consult. Perhaps there is a local authority in charge of monitoring earthquakes, for example. Any chance there is road construction or some other type of development where they are blasting rock? Even miles away, that could be felt.

If you exhaust all the possibilities (small localized quakes, blasting etc.) you might want to hire an expert to inspect your house and find out what is going on. Especially if someone who knows what they're talking about says there is karst in your area. But I'd rely on the services and advice of local government that you already paid for, first.

Actually I'm in Canada, but only 8 minutes from the US border which basically puts me in the Pacific Northwest. It's not Karst topography up here. We're in low river delta/coastal plain land. Not really sink-hole land by any means. But, we're wedged right between two small creeks. And there is an active pond about 100 meters behind the building that drains into the creeks. We have had a lot of heavy rain recently after some deep frost. With the water levels rising and infiltrating the ground, is it possible we're experiencing the first signs of subsidence?

When it comes to speaking with officials here you might as well be banging your head against the wall, but I'll give it a try. It's Canada after all - land of passing the buck. I'll start with City and go from there. We did have the house inspected before we moved in. The guy didn't find anything of note. Some cosmetic deficiencies, that was all.

This is a little scary. Do you own your home? I recommend that you contact your duplex neighbor, and consider hiring an attorney together, especially if both of you are purchasing your homes. Perhaps there is an organization that helps in a situation like yours? Was a real estate agent involved? Or, if construction work elsewhere is causing problems then the responsible parties need to be aware of the damage and renumerate you for repairs. Thank goodness the home is new, there is no issue with prior condition. Take lots of pictures.

If your property is sinking, you will need to prove it. Buy a GPS that measures altitude vis a vis sea level and take measurements on all four corners of the building. You can also hire a structural engineer to measure the interior in a like manner, but I think they measure the interior relative to the foundation, not the earth. This shouldn't be too expensive.

You may need to file suit against the builder, whoever filled in the pond, and possibly the real estate agent, plus the inspector. Settling with age takes years and even then the movements are slight. What you are describing is extremely serious and may mean that your home is falling apart. Please check your gas lines. If the pond wasn't filled in properly, you need to move because things will not get better, time rarely corrects construction or land problems.

I'm very, very sorry this is happening to you. Please don't wait until another incident. It might result in harm to you and your son. If your house is built on slowly shifting ground, I would walk away from the mortgage if you cannot resolve this with your builder. The government might condemn the property if it can be shown that it is unstable. Your mortgage lender has an interest here, contact them as well-if you are buying the home. Good luck!

You might also look for an expert in underground water movement, perhaps a local university Civil Engineering department if not a consulting firm? Post this in the building a home forum for more advice.

This sounds scary to me. I think calling the bldg inspector as well as your builder is the thing to do ...IMMEDIATELY. You could consult a structural engineer, but, do it immediately, because it doesn't sound like your family is safe in that house. There is probably a 1 yr new home warranty, so if it is structural you should be covered. I don't live in an area that is prone to earthquakes, but I do wonder if you could be experiencing aftershocks still from the earthquake in December. Whatever it is, it's important to get the bldg inspector, structural engineer, and your builder out immediately.

The ball is rolling on this. We bought the home pre-construction. It's part of a planned community with 90-some units. The builder sold the home through a contracted sales agent. There are other problems onsite. Deficiencies that need to be addressed by the builder as part of the 1-year new home warranty. The builder is dragging his heels on these deficiencies. One is rather significant - the owner has been fighting with the builder on this since he moved in back in late summer.

With Canadian laws, I wonder who is responsible for what? Initial contact with the builder shows that they likely didn't do a ground survey before starting construction. Are we as the buyer liable for not obtaining that information prior to closing the deal? I am aware of the buyer-beware clause but this kind of information is often difficult if not impossible to obtain. But is there not a reasonable expectation when buying from a builder that said builder has done his due diligence before beginning construction?

A pre-purchase home inspector is looking for obvious visible problems, and if there were cracks in the walls at that point, he would have made it an issue in his report, but it didn't show up until later. Those guys don't do structural analysis of the ground or compacted fill under your house, nor are they qualified to do so.

There has to be a local agency responsible for building code enforcement and inspecting/approving each stage of the construction on each home in the development. Find out who approved the plans and what they saw while inspecting installation of the foundation.

I don't think a GPS is going to be accurate enough (to the fraction of an inch) to be able to know if your house is moving until it's REALLY moving. It would be better to have a surveyor locate a corner relative to a nearby solid benchmark, and document that. I don't know if that's worth the expense or not.

I'd get a building foundation expert/structural engineer looking at it first. Maybe that's a local govt building inspector and it won't cost you anything, but get it done soon.

And document, document, document. Keep a diary - dates of calls, who you talked to, what they said, and every time the house rumbles or you notice a new or widening crack.

That's what I'm doing - documenting everything. I've contacted the city's building inspection department and the builder. So far though, no response from either party. I'm looking for a structural engineer to come out and provide guidance.

I received a reply from the builder and they are not taking any kind of responsibility for this. They are saying it is 'traffic' related, or that the neighbor (who wasn't home both times) is causing the vibration. If we want to pursue this we have to hire an outside contractor, at our expense, and go from there.

Get a Real Estate Attorney. Don't waste your time trying to deal with someone who won't address a problem unless they are forced to.

Neither traffic, nor a neighbor, should be able to cause drywall to crack in a properly built house.

Do talk to your shared wall neighbor and see what they've noticed. And just to be sure, you know that it's not something like an unbalanced washing machine next door--the spin cycle can come on well after someone leaves the house after all.

(Any aftershocks would be reported by USGS.)

a very similar thing is happening in Marana , AZ. Part of a development was built over a filled in quarry. Now the land is settling probably due to not being compacted properly. See the story here: http://www.tucsonnewsnow.com/story/30847695/marana-subdivision-sinking-into-old-stone-quarry

May want to contact other neighbors to see if they are having problems. )Can you say class action suite? )

Yes, this is exactly what I'm afraid of happening here. I will send this to our neighbors and talk to them. Here in Canada the MO of builders is to declare bankruptcy at the first sign of trouble - so many home owners have been left homeless because of these unscrupulous builders.

It sounds like the house was built on unstable earth, poorly/incorrectly excavated. This happened to a fiend of mine in Indiana. 3 homes total were involved. Have a professional check it out. The builder of all 3 homes was responsible. The owners were paid and moved on. The ground was stablized and the homes resold.

They may have (should have) done geotechnical borings before building to evaluate the type of soil and its natural state of compaction. This is how designers figure out how to put a building in a given spot. The results (which should be in a report from the geotech contractor) are used by architects to determine whether to further compact soil, remove it and replace it with something more stable, and what kind of foundations will be needed to hold up the desired building. I don't know what would be required by regulation in your area but if you get into legal action with the developer, you will want to demand a copy of this report - if there is one.

In 2009 i destroyed a foundation of old demolished house and shed with a 10 kg hammer. Guess what i found!?

Glass bottles and jars were in foundation as well as weak and thin pieces of rock! This ain't a joke! I destroyed that foundation very easily. Builders are snakes these days. Who knows what they put in your foundation so they invest less money? I would move because your house could collapse anytime. SAFETY FIRST! That's very serious as your water and gas pipes could easily perforate making a catastrophe with casualties.

Very troubling story. You need to obtain a copy of the building prints, which will document structural details that you can use in your pursuit of professional counsel. I am just across the border in the states, and the codes here specify the bearing soil compaction rate minimums required to build upon, and in the case of having to fill, the filled material requires compaction tests by a soil engineer. It could be the soils, the construction quality or both. New construction settling is an over used phrase, too often used to dismiss what is actually poor workmanship & quality control during the build. Minute hairline sheet rock cracks occasionally occur, but large cracks and moving furniture? Very very concerning.

Seattle, Washington, USA is in an earthquake zone. In fact, the zone extents up through the coastal part of Alaska and on along the Aleutian Islands. The Cascade peaks in the US are all volcanoes sitting on a subduction zone where the Pacific plate dives into the bowels of the earth. The Pacific plate slides under the continental plate off shore in the Pacific Ocean. Small aftershocks and tremors are common up to a year or more after a main shock. If you live in that area, you have felt an aftershock.

If your building is on fill that was not properly compacted, you can expect settling problems. Often, signs of settling first appear in concrete garage and basement floors. Some cracks in these floors are to be expected. I have a settling crack that appeared in my garage floor about 25 years after it was built.