Determining the Best Type of Fastener to Use For Outdoor Furniture Construction

If you want to learn about selecting hardware forWhile stainless steel fasteners are the most rust
your next outdoor furniture project, then you'll wantresistant, they are also the most expensive of the
to read this article. Specifically, I'll be telling you aboutoptions we are discussing. However, using stainless
what type of hardware will perform best, why thesteel fasteners will add years of life to your
type of metal used for fasteners and the finish usedfurniture. In the respect, they are an investment
are important considerations, and how properlythat will pay out for years to come.
protecting or limiting exposure of your furniture toBrass
wet and winter conditions can increase life span.I have seen brass used in some commercially
After you're done with this article you will understandproduced outdoor furniture, but do not recommend it.
that the best choice of hardware for your outdoorWhile brass does not form red rust, and is well suited
furniture project is dependent on furniture style,for many wet applications such as toilets and sinks, it
material used for construction, selected location fordoes tarnish and corrode. It is also very susceptible
the furniture and budget.to the tannic acids in wood, which will cause it to fail
Selecting proper hardware for your furniture will helpmore quickly. Brass screws in particular do not have
ensure a long life span, as well as improve the overallsufficient strength for outdoor furniture applications.
appearance of your furniture. Part of the problem isOutdoor or deck screws
knowing what hardware to select when there are soIn the past several years a number of manufacturers
many options available at the hardware store. Thehave introduced outdoor fastening products
typical Lowes or Home Depot carries a hugespecifically marketed for deck building. These will
selection of stainless steel, hot dipped galvanized,typically be green, gray, tan or brown. These screws
bright galvanized, plain steel, coated steel and brassare either ceramic or plastic coated to delay the
bolts, nuts, washers and screws. Each type ofmetal reacting with the wood acids. The specific
fastener is suitable for certain applications, but not allcoating methods are proprietary to each
are ideal for outdoor furniture applications. manufacturer, and can be a combination of
In fact, choosing the wrong fasteners can greatlyelectroplated galvanizing and plastic, or a baked on
shorten the lifespan of your furniture, contribute toceramic.
rot of wood furniture, cause unsightly staining, andI have used these fasteners in furniture applications
even make your furniture unsafe to use. and they perform just fine. Unfortunately, I have not
One thing that needs to be noted right up front is,come across bolts with this type of finish. The brand
do not ever use unprotected steel fasteners forof screw I used was Deck Mate, and they were
outdoor furniture, They will rust very quickly, and theavailable in tan and brown, so that the color can be
steel will react with the tannic acid in the woodselected to better match the wood being used.
causing streaks and staining. The tannic acid actuallyThese screws are ceramic coated, and the
speeds up the corrosion of the fasteners. Have youmanufacturer provided a coated bit for installation,
ever seen a wooden fence with black streakswhich was designed to not damage the ceramic
running down the boards from the nails? This fencecoating at the screw head. If you choose this type
was installed with the wrong type of fasteners. Theof fastener, be sure to compare the cost with
same thing will happen to your furniture. Even worse,stainless steel, as the price will vary. If the stainless
as the fasteners rust, they will speed up the decaysteel is reasonably comparable in cost, it would be
process of the wood around the rusted fasteners,the recommended fastener. 
ruining your furniture and making it potentially unsafeAlways be sure to read the manufacturers
to use.specifications on the box to be sure that the screws
Hot Dipped Galvanizedare suitable for your application. 
Screws and bolts treated by hot dipped galvanizingOther Considerations
are specifically designed for use outdoors.If you are building furniture that will be located on a
Electroplated galvanized or bright galvanized fastenerscovered porch or patio where it will be protected
ultimately will not hold up as well as the hot dippedfrom the elements, the concern will be the interaction
galvanized hardware. Zinc is used as a coating in bothbetween the wood and the fasteners, much more
methods, and acts as a barrier against the elementsso than the weather. Furniture that will be exposed
and the tannic acids in the wood. to the elements all year, such as a garden bench, or
I strongly recommend only using screws or bolts inan Adirondack chair in the corner of your garden, will
the construction of outdoor furniture, however. Thehave to be constructed with much more care and
galvanized finish on nails, either electroplated or hotconcern to ensure that they hold up more than just
dipped, can easily become damaged while hammeringone or two winters.
them in, exposing the nail head to the elements andAdditional considerations must be made beyond just
allowing them to begin rusting quickly. the choice of what type of fastener to use, though
Adequate care must be taken when installingthis is very important. For example, fasteners should
galvanized screws. Drill pilot holes in hardwoods, andnot be located where water where collect and sit on
be sure to use a bit that is not worn and susceptiblethe fasteners for an extended period of time. The
to skipping in the screw head. For whatever reason,screws that attach the seat slats to an Adirondack
the galvanized screws seem to not be as wellchair are a prime example- typically these screws will
tempered as other steel fasteners, and are morebe countersunk below the surface of the wood. This
likely to either snap off or have the heads strip outwill allow water to collect in the screw holes,
while installing them. Due to the allowance requiredshortening the life span of all but stainless steel
for the hot dipped coating, galvanized bolts do notfasteners, and prolonging the exposure of the wood
have as tight of tolerance on the threads, and areto water, which will increase the rate of decay. In
more likely to strip if over tightened.applications where the furniture will be exposed to
Hot dipped galvanized fasteners are a fine choice forthe elements year round the screw heads should be
many outdoor furniture applications, includingdriven flush with the surface of the surrounding
Adirondack Chairs, but are not the best choice forwood. 
use in woods, such as teak.Construction and design of the furniture are also
Stainless steelimportant considerations. Are the horizontal surfaces
Stainless steel is the best choice for use in woodsof the furniture constructed in such a way that will
with higher levels of tannic acid, such asallow them to shed water, rather than collect
teak. Stainless steel is an alloy or blend of steel,it? Think of a picnic table with a slatted or board
nickel and chrome. The ratio of the other metalstop. The gaps between the boards allow water a
with the steel determine the weather and corrosionway to run off the top and not pool up. 
resistance of stainless steel. Because the steel isConclusion
mixed with other softer metals, the stainless steel isStainless steel is usually the best choice for outdoor
not as strong, so predrilling of screw holes is highlyfurniture applications, though the cost may be
recommended in all applications, and essential inprohibitive for some. There are other less expensive
hardwoods such as teak and mahogany. The addedfastener options available that will perform
corrosion resistance more than outweighs anyacceptably. Do not use unprotected steel fasteners
shortcomings that the metal may have, especially infor outdoor furniture applications under any
outdoor furniture applications. circumstances.