Exterior Finishes - CRA | California Redwood …

1 Exterior FinishesCalifornia Redwood is one of nature smost maintenance-free buildingmaterials. It has a natural resistance todecay and insects. Redwood s naturalstability means it shrinks, warps, andsplits less than most other woods. Inaddition, no other wood takes and holdsfinishes better than Finishing Tips Apply Finishes on windless days. Tem-perature should be between 50 and 70degrees Fahrenheit. Surfaces should be clean and dry New structures built with unseasonedwood should air-dry one month beforefinishing. Back-priming is recommended for allexterior Finishes , particularly paints. Don t use wire brushes or steel wool asmetal particles may become embeddedin the wood and can cause stains. Usestiff bristle brushes. Use Finishes recommended for woodexteriors. Follow manufacturer s directions andread warnings on toxicity Don t mix incompatible materials. Finishfailures may result from mixing incom-patible products or applying them overone another.

2 Moisture is the most common cause of finish failures, so use proper vaporbarriers, air vents and flashing in newconstruction. Saw-textured Redwood holds stains,water repellents and bleaches up totwice as long as smooth-surfaced wood. Redwood grade marked Certified KilnDried will provide the best finish retentionavailable. To avoid nail stains, use stainless steel,aluminum or top quality hot-dippedgalvanized nails. Periodic rinsing with a garden hose willremove dirt and grime from build-up can be removed byscrubbing with a bristle brush with asolution of warm water and a milddetergent. Rinse afterward. Splash lines can be minimized by anoccasional hosing of the unaffectedarea, which will even the appearanceof the Finishes Not Recommended Varnishes and polyurethanes crack andpool when used for exteriors. They aredifficult and expensive to apply anddeteriorate quickly Removal is expen-sive and difficult.

3 Pure oil-treatments such as boiledlinseed oil, are not recommended onexterior Redwood as they tend to promotemildew growth. Quality oil-basedfinishes,including those based upon linseed oil,contain mildewcides, and are appropriatefor use on Exterior Redwood . Shake and shingle type paints do notlast well on Redwood lumber Water Repellents with Mildewcide Clear Finishes that modify weath-ering characteristics and letcolor and grain show or Weathering Stains Low maintenance, naturalappearance with a gray-toned StainsPenetrating Finishes available in a variety of semitransparentcolors including severalredwood hues. Oil-based stains are Body StainsFilm forming Finishes avail-able in a wide variety of opaque colors. Oil-based stains are , attractive Finishes fortraditional exteriors. Qualitypaints are generally worth theextra FinishesNatural Appearance FinishesDescriptionPigmented StainsPaintsUsesEffectApplicationMainten anceCertified Kiln Dried or air sea-soned siding, fascia, trim,decks, fences, garden struc-tures, commercial and containingtoxic mildewcides are not rec-ommended for seating, tablesor Kiln Dried or air sea-soned siding, fascia trim,decks, fences, garden struc-tures, commercial and containingtoxic mildewcides are not rec-ommended for seating, tables,or Kiln Dried or airseasoned siding, fascia, trim,decks, fences, gardenstructures and furniture,commercial and industrialbuildings.

4 Most semitransparentstains contain Kiln Dried or air sea-soned siding, fascia, trim,decks, fences, garden struc-tures and furniture, commercialand industrial Kiln Dried siding,fascia, trim, some garden struc-tures and furniture, commercialand industrial buildings. Notrecommended for decks andwalking or seating : For air-seasoned orunseasoned siding use astainblocking latex primerformulated for weather and mildewattack. Stabilize Redwood scolor at buckskin tan. Helpseliminate Redwood s naturaldarkening period. Areas ex-posed to direct sun and rainmay eventually bleach to for low maintenanceand give Redwood a uniformlygray or naturally color in a finish that letswood breathe naturally Semi-transparent stains let the grainshow through but present a uni-form single color. The amount ofpigment contained in stains willvary according to color in a finish thatlets wood breathe stains will obscure thegrain but highlight the textureand have an appearance morelike attractive colorfulfinishes which obscure grainand texture of the with brush or roller.

5 Lapmarks and brushstrokes will notshow through. Two coats rec-ommended for new wood. Forbest results, coat sawn ends,backs and edges before nailingin Labels: Mildew-cides may be with brush or roller. Lapmarks and brushstrokes mayshow through as many includegray pigment. Use one or twocoats according to manufac-turer s directions. Bleaching is aided by sunlight andmoisture, so it may speed the process to periodicallydampen surfaces with a finespray from a garden with brush for best re-suIts, next best is a roller. Avoiddrips and lap marks. Two coatsusually required for new wood follow manufacturer s best results use a next best applicator is aroller. Avoid drips and lapmarks. Two coats usually re-quired for new wood followmanufacturer s with brush for bestresults, roller is next best appli-cator. One prime coat and twotop coats are recommendedfor new wood. Back-priming is highly recommended.

6 Useoil- or alkyd based stain-blocking primer. Acrylic latextop coat is is required afterold finish has lost its effective-ness. In humid or harsherclimates, reapplication may berequired every 12 18 applying, wood may be restored to its natural coloras described on back oils and stainsprovide nearly maintenance-free performance. Reapplyfinish only if wood begins todarken or bleaching is refinish coat should may be necessaryevery 3 5 years. Color in pig-mented stains may wear awaygradually after brushing with a bristlebrush will help remove old finishin some spots. One refinishcoat is usually may be necessaryevery 3 5 years. Color in pig-mented stains may wear awaygradually after brushing with a bristlebrush will help remove old finishin some spots. One refinishcoat is usually may be necessaryevery 7 to 10 years. Paint filmsthat are too thick tend to pooland crack. Sand or scrub withstiff bristle brush.

7 Paint andvarnish removers may also beused. If sanding, countersinkgalvanized nail heads toprotect their Association2 /01405 Enfrente Drive, Suite 200 Novato, California 94949 Telephone 415-382-0662 Fax 415-382-8531 Toll Free 888 our renewable resourceFinish RestorationDirt and Dust may build up to the pointthat a mere rinsing with water from ahose will not remove them. A mild deter-gent and warm water will generally re-move stubborn dirt and appears as dark spots or gray,fan shaped spots on the wood infested areas may appear uni-formly gray or black. To remove a mildcase of mildew, scrub with a mildcleanser or detergent. Next rinse with ahousehold bleach to kill surviving rinse with water. When applying anew finish, be sure it contains a : Household bleach shouldnever be mixed with detergent containingammonia. Fumes can be severe mildew infestations, scrubwith a stiff bristle brush using a solution ofone cup of trisodium phosphate, one cupof liquid household bleach and one gal-lon of warm water.

8 Rinse thoroughly. Ifnecessary, follow with an application of4 ounces of oxalic acid crystals dis-solved in one gallon of warm water in anon-metallic container. Apply evenly witha soft brush. When wood dries, rinse : Oxalic acid is poisonous,but not dangerous if precautions aretaken. Wear rubber gloves. Avoid contactwith skin or Stains are an unsightly problem thatcan be avoided by using stainless steel,aluminum or top quality, hot-dipped gal-vanized nails. The cleaning method de-scribed above for removing heavy mildewstains is suggested for nail stains. To helpprevent recurrence, countersink the nailsand swab the holes with a water repel-lent. When dry, fill the nail holes with anon-oily wood filler for natural Finishes ,or putty if the wood is to be Peeling,blistering and flakingoccurs when moisture under a non-breathing film finish destroys the film sadhesion to the wood. A properlyinstalled vapor barrier is the recom-mended way to control this barriers should be on the warmside of the wall.

9 Problems also may becaused by faulty surface preparation, orthe use of incompatible Redwood s ColorDiscoloration of paints and Finishes mayoccur when extractives are dissolved inwater and leach from the wood. Thisdiscoloration can also result frommoisture migrating to the surface ofunseasoned lumber. To remove extrac-tive stains and to restore the newappearance to weathered wood, followthese steps. Scrub wood with a bristlebrush and a solution of one cup tri-sodium phosphate (TSP) and one cup ofhousehold bleach to a gallon of apply a solution of 4 ounces oxalicacid crystals dissolved in one gallon ofwarm water. When wood dries, rinsethoroughly with FinishesWhen a finish has deteriorated to thepoint of cracking and peeling or someother finish ailment, it may be desirableto remove it before effectively removes pigmentedstain Finishes . Galvanized nail headsshould be set below the surface beforesanding to protect the coating andprevent nail blasting is an effective way ofremoving old finish and grime andpreparing for a new finish.

10 A fine, high-powered spray effectively removes loosematerials without damaging the use of a paint and varnish removeris another way to remove a kinds are available. Beforeusing, test the preparation on a piece ofnew, clean Redwood to make sure it willnot discolor the wood particularly if anatural finish is to be used. Film-formingfinishes can be removed with a paintand varnish remover. Heat is anothermethod of paint removal.