Elev. cert, no BFE

Flood Zone A is always a PIA, especially on existing structures. Make it a manufactured home and its worse.

Around here the BMF needs to be 2' above HANG (FEMA says 1'), with the tricky part being the 'N' - natural. You won't need to run levels, because there is no BFE established.

Get paid in advance because your client is not going to like the rate increase when it is determined they are not in compliance, unless they raise thier house 2 or 3 feet.

Good luck

I think the owner can fill one out without elevations by measuring up from existing ground to finished floor in an A zone.

Thanks Wayne,

What's HANG & BMF? I'm having a BF because I'm a DUMMY......

I am doing one today in a similar situation. I contacted the county flood plane administrator and was told to mark the base flood elevation as Zone A rather that using an elevation.

I would contact the community floodplain official and ask about the bfe..if they have not established a BFE, I would prepare the elev cert and denote NA for BFE and under comments explain that no BFE is established in zone a per that official.

Ditto contacting the Local Flood Official.

As a last resort, there's always the Quick2 program from FEMA.

> What's HANG & BMF?

Never a dummy...;-)

HANG - (Section E) Highest Adjacent Natural Grade. Some times it is just HAG - Highest Adjacent Grade. Our county requires HANG, but I think FEMA is good with HAG. It's the 'natural grade' that can get tricky on developed sites.

BMF - Bottom of Main Frame (of a manuf. home). Typically 15-18 inches below the floor. That must be 1' above BFE or HANG (2' here), which puts any manuf home about 4' above grade.

On the FEMA website there is an entire booklet available for manufactured homes. It addresses all the requirements for skirting, anchorage, flood openings, and where the owner can buy their KY jelly. Don't forget that unless you are a PE, don't talk about anchorage or foundations - just the elevations

As a side kicker, in Section F, the owner can do their own. I've walked away from Zone A jobs because I didn't want to be involved, and let the owner know they could do it themselves - thus they are liable. Your $700 around here would be about right.

Elev. cert, no BFE, be careful

Be aware the real issue. Is the home going to be inundated in the event of a significant flood.
No BFE nor depth of flood can be estimated without performing both the hydrologic and hydraulic analysis. Even then the model has to be "truthed" with empirical observations.

This is not a surveying excercise, it is an engineering problem.

Flood plain administrators are an important contact, BUT, and its a very big BUT, flood plains administrators are often not engineering experts and are instead very often persons who from a very different background. Often they are planners, building officials, heck I even know one who is a city clerk. They usually have a fair understanding of the National Flood Insurance Program (NFIP) but are very limited when it comes to understanding the true meaning of things such as Zone A w/o BFE.

Determinination of a BFE must be based on the best available data. FEMA has included the ability for a landowner to simply certify as to his FFFE above HANG. I recommend against using this method as it rarely results in an accurate rating.

Instead, I highly recommend that either you or the landowner consult with a civil engineer experienced in hydrology and BFE determinations.

The main point being that an understanding of volume and velocity of flow for the particular site must be developed in order to determine the risk factor relationship to topography.

This type of work is becoming an area in which I have been focusing my practice. As both a PE and LS who has been involved in large scale flood mitigation projects, I must reiterate, this is not a surveying problem. It is an engineering problem. Do the landowner a favor and help them understand that also.

Thanks everyone!

Contacted floodplain Admin for county, who indicated they in fact had a FIRM but no BFE. First (& second & third) search at MSC indicated no past, present or future maps. Fourth time hit pay-dirt, no FIS, but map confirms we're in Zone A. Told 'em to fill e-cert out their own selfs.

Now I've wasted an hour & 1/2 of daylight.....

I hate that FEMA website.

Thanks again,
SS

Elev. cert, no BFE, be careful

While you are quite correct that it's an engineering issue, have you met any property owners that were eager to pony up the consulting fee for getting cross-sections and modeling done to determine a BFE, especially those folks who just found out that they have to get flood insurance and live in a trailer? I haven't. While that is the correct way to go about it, they all want the cheapest route and will usually, like water, go the path of least resistance.

Elev. cert, no BFE, be careful

> While you are quite correct that it's an engineering issue, have you met any property owners that were eager to pony up the consulting fee for getting cross-sections and modeling done to determine a BFE, especially those folks who just found out that they have to get flood insurance and live in a trailer? I haven't. While that is the correct way to go about it, they all want the cheapest route and will usually, like water, go the path of least resistance.

Glenn,

I have met quite a few actually. its been a big part of my business. Although most are folks who have some investment of value in their home greater a trailer.

Those with trailers actually have it easy since it doesn't cost much to jack them up.

Educating any of them on why an engineer should be involved is not unlike that of how we speak to owners about property boundaries and having them properly surveyed.

Take the case where the county comes and says your trailer is in their right of way and you need to either move it off or pay them a $4k a year encroachement fee. The county can't tell you where the r/w line is because they haven't actually determined it, so that leaves you with either completely removing the trailer or hiring a surveyor to determine the r/w boundary.

Pretty easy to educate the owner why an accurate survey should be performed so the owner can know how far to move the trailer or if it isn't actually even in the r/w.
Consider also educating the owner on the fact that the county is going to build a road one day with little notice and they will wipe out your trailor and all your family's heirlooms, photos and kids toys irregardless if they've paid the encroachment permit fee or not. Sure, they may give you some money for the replacement of the trailer, that is if you've been paying the $4k/yr encroachment fee. But you'll never be able to replace those photos of your 5-yr old aspiring quarterback bouncing a perfect spiral off of the back of your monster-in-law's noggin. Those are irreplacable and no amount of money will replace them.

Same with a BFE determination. Take the shortcut and rely on some bs approximation, but don't come crying to me when your trailer goes floating down the creek with your prize collection of beer bottle caps.