There are basically two types of tiny house owners. There are those that want to build/buy one and travel the nation. There are then those that want to park it for an amount of time without mobilizing. This article is geared towards the latter. Now there are several reasons for owners to want to anchor their tiny house down. Seems odd, yes, since tiny houses on wheels are designed to be mobile. However, circumstances sometimes deter that idea and call for special attention to immobile details. Whether it be hurricane force winds, tornado threats, small mudslides, or even small flooding, it is best to be prepared to keep your tiny house from involuntarily moving. This doesn't even begin to speak to the municipalities that require homes on wheels to be anchored down and strapped down as a more traditional mobile home would be. But what is an anchoring system, where do you get one, and just how does it work?
There are three parts of the basic anchoring system:
- The auger anchors, or steel rods several feet long that screw into the ground. Only a few inches of the anchors should be above ground level; otherwise, they won’t have the holding power they’re designed for. These can either be set into wet concrete so as to give strapping points beneath the tiny house or they can be "screwed" into the dirt around the perimeter of the house.
- Steel straps. They fasten around the frame of the trailer and are attached to the anchors with adjustable bolts. (NOTE: It’s hard to guess how many straps your tiny house should have, because the numbers have been set by engineers and changing standards during the past 20 years and are for sticks ‘n bricks homes, to boot.)
- The piers that the home sits on. They’re usually made of cinder blocks stacked on a concrete pad, although a few homes may be on solid concrete piers, especially if they’re elevated several feet above the ground. If these are used they can allow for the wheels to be taken off the tiny house and the stabilizer (or scissor) jacks to be disengaged.
Let me point out that the purpose of anchoring is not because the trailer may or may not be stable as is, but rather because in certain weather situations wind and water can get up under the trailer/house and literally lift them up and relocate them. To avoid this you need to anchor your home down. According to most mobile home manufacturers a trailer up to 40ft. should have 2 diagonal ties per side and 3 vertical ties per side.
TYPES OF ANCHORS
Anchors are available for a number of soil conditions including concrete slabs. Auger anchors are perhaps the most common and the easiest to locate and purchase. They are designed for both hard soil/clay and soft soil. Rock anchors or drive anchors allow attachment to a rock or coral base. This type of anchor is also pinned to the ground with crossing steel stakes. If you will be pouring a concrete base, you can install a concrete anchor first.
You need to know your soil type to select the right anchor. Soil classifications usually include:
- rock/hard pan
- sandy gravel
- heavy sand
- silty gravel
- silty clay
- clayey silt
- uncommitted fill or peat/organic clay
- Remember, auger anchors (screw-in anchors) can be installed manually by inserting a metal bar through the top of the anchor for added leverage or with a machine designed for this purpose. It’s important to screw this type of anchor in. Do not dig a hole to install. It will not function properly.
HOW TO INSTALL
LEVEL YOUR TINY HOUSE. Make sure your trailer is level before anchoring it to the ground.
DETERMINE YOUR SOIL TYPE. Merely looking at the ground under your home isn’t enough. Some types of anchors need to be installed five feet deep. If you will be attaching your tie-downs to a concrete foundation, make sure it is at least 4 inches thick.
SELECT ANCHORS. Talk to a supplier or installer for advice. Your soil type will determine the type of anchor.
SELECT HOOK UP. Depending on your tie-down system, over-the-top or frame, select the appropriate hook-up and tensioning device. Make sure the entire system is certified to a 4,725 pound capacity.
INSTALL ANCHOR. There are specific instructions with anchors. For a vertical tie-down, the anchor is installed vertically. For a frame/diagonal tie-down, the anchor can be installed to the same angle as the tie-down – at least 40 degrees. The anchor can be installed vertically if you also install a stabilization device to keep the anchor from moving sideways. A metal stabilization device can be attached to the top of the anchor and buried in the ground. Another option is to pour a concrete collar around the top of the anchor. The collar should be at least 10 inches in diameter and 18 inches deep.
ADJUST TENSION. Alternating from side to side, adjust your tie-downs to the appropriate tension. Adjust one side of your tiny house and then the other.