IMAGES: VERSATILITY AND QUALITY OF TOTARA
For more images, see Boatbuilding page.
TOTARA TIMBER QUALITIES AND GRADING
(See Disclaimer below).
From the status of “the timber that built New Zealand” with the wholesale exploitation and destruction of forests it is now a rare and almost forgotten timber except as a much sought-after iconic timber for carving and crafts. Heartland Timbers has spent several years researching and experimenting with totara and drawing on local knowledge, historical records and some more recent research. However, our advice is subject to the Disclaimer below. Following is a summary of our findings to date.
At 12% moisture content [NC Clifton, NZ Timbers 1990, pub. GP Books): Native softwood like matai, rimu, kauri, etc. Density: 480kg/m3. Modulus of rupture: 62 MPa. Modulus of elasticity: 6.4 GPa. Shrinkage from green, tangential: 4%, radial 2%.
General: Unlike all other common native timbers, the entire log of totara is very durable for all indoor and covered applications and some external uses. Our logs are over 150 years old and 75 – 85% heart. The heart timber is extremely durable and renowned for all outdoor uses including fence posts. Posts and house piles have been known to survive for over 100 years, making totara one of the most durable and versatile timbers in the world. Totara contains minute crystals of a unique anti-fungal and anti-infestation resin called totarol, a very valuable therapeutic and antiseptic substance which is the basis of a small industry extracting it as a very valuable oil. All of our products are therefore organic, chemical free and safe for all uses indoors and outdoors.
“Sap” totara: Unlike all other commercial NZ native timbers, the outer rings of totara have long been known to be very durable when used in virtually all applications except in the ground or constantly soaked in water (except for sea water which has a preservative effect on all timbers). . For more recent investigations into this please see Paul Quinlan’s excellent research for the Northland Totara Project, kindly contributed by the author through this link: https://www.heartlandtimbers.nz/wp-content/uploads/sites/173/2020/07/Totara-sapwood-and-borer-final-report-31-Jan-2017.pdf . Please note his disclaimer from any liability, and our similar disclaimer, with our opinions and findings being the genuine result of genuine research and experience but not providing any absolute guarantees.
We add however that our South Westland timbers are much older and more mature than the regrowth or farm forestry timbers of Northland. The timber is probably denser and more resinous; much slower growth in cold and immense rainfall and flooding conditions also results in tighter growth rings and probably higher water resistance; and that the unique hybridization of some or our trees (with totara var. Waihoensis and Hall’s Totara) might also create unique properties as yet unstudied. Practical experience in logging and building has shown us that the external sap on South Westland logs lying in the bush for many years does rot out in contact in the ground, but where dry and ventilated, remains intact and borer-free. When properly seasoned under cover, the preservative resins presumably become concentrated and locked in. From research and experience, we conclude that sap totara has a unique durability and we are confident that it can be used for all interior or sheltered locations and as exposed exterior surfaces, with proper installation to ensure it does not accumulate trapped water for long periods. If in doubt, a coating of exterior oils or sealants should be used, as in the exposed marine uses illustrated on this website.
Workability: For the woodworker, totara wood is variously described as “workable”, “gentle”, “easy”, “lovely”, “cuts like cheese”, and “benign”. It is the best of timbers for the craftsman, carver, sculptor, boatbuilder. Now thanks to the gift of windfall, its potential for all buiding uses can now be revived.
Feature and character: Our totara is all regarded as “feature grade” to some extent given the exceptional character and beauty of the natural timber. Features otherwise graded as “defects” or “flaws” include encased bark, enclosed knots, ancient insect or fungal damage; ripple, “shake”, mottle, wave, and other beautiful features. As all of the timber is borer- and fungus-resistant and exceptionally durable, none of these variations reduce the inherent quality of the timber, and in our view greatly enhance it. All surface marks or indents can be easily and permanently be filled with epoxy mixes or other fillers, including sawdust/epoxy mixes as “liquid wood”.
However, there may be buyers who prefer a plainer look, so we are separating boards with heavier featuring to sell together with the plainer timber or separately for mixing in or special character areas.
TOTARA PROPERTIES:
Heartland Timbers has been fortunate to have salvaged the unique South Westland variant of Podocarpus Totara var. Waihoensis, sometimes hybridised with the giant Lowland Totara and smaller Hall’s Totara, but all benefiting from the presence of totarol resin and other virtues of this world-renowned and now rare native timber. Much has been written about the legendary durability and qualities of Totara, and its iconic status in Maori culture and pioneer settlement. We are now fortunate to have the knowledge of a life-time of study and experience in the beautifully illustrated and deeply researched work by Philip Simpson: “Totara, a Natural and Cultural History” (publisher AUP, 2017), a vast and comprehensive resource of every aspect of this iconic tree.This work is highly recommended to all those interested in the building of New Zealand, tangata whenua histories and culture, botany, ecology and NZ colonial settlement and culture. It supervenes previous brief studies such as “New Zealand Timbers” by NC Clifton (GP Books, 1990), previously the leading authority. Totara has been revered by all NZ cultures throughout living memory and was unfortunately exploited to near-extinction during early settlement and subsequently forgotten and misunderstood.Totara has been revered by all NZ cultures throughout living memory and was unfortunately exploited to near-extinction during early settlement and subsequently forgotten and misunderstood.Totara has been revered by all NZ cultures throughout living memory and was unfortunately exploited to near-extinction during early settlement and subsequently forgotten and misunderstood.
For further information about the “Heart and Soul of Totara”, please see our “Totara Wood work and Boat Building” Page.
Durability:Totara’s durability is legendary. Despite it’s lightness, the heart timber is ground-durable and the whole log is entirely insect-borer and fungal resistant, including the outer sap timber when dry and rarely shows signs of “sap stain” or mould unless left on wet ground for years. Totara was often regarded as a hardwood because of its exceptional durability and relative heaviness when green (partly explained by the absorbency of the timber). In fact it is relatively soft like kauri, kahikatea and sap/colour rimu or radiata pine. Totara is the ideal wood for patching and filling rotten sections of hardwoods, kauri or rimu etc which do not otherwise need replacing. Photos on this website show instances of this in repairing kauri and jarrah beams with end rot or surface rot in damp conditions, and filling with “liquid totara” made up of various sawdusts and chips mixed with epoxy resin, blended with replacement blocks of totara for large areas of rot. Kauri in particular, used widely for boat-building has nothing like the durability of totara, and gradual replacement with this superior timber is recommended to restorers and repairers of all exterior woodwork.
Weight and density: totara dries from up to 700 kgs per m3 as green logs, down to 480 kgs at 12% humidity or less when fully seasoned. However, being tight-grained, it is also strong, so stiff it holds its shape as milled and is renowned for its stability and fine grain.
Stability:The bending, warping and buckling for which some native timbers are renowned is entirely absent. Amazingly, it holds its shape as milled, forever it seems; fortunately it mills very straight and can be milled into wide planks and flitches with minimal warping or cupping. This is partly due to the exceptionally low radial shrinkage of just 2%, the lowest of all common NZ native timbers, resulting in a timber with very little movement in log form or sawn timber during seasoning. It is remarkable that a 500mm flitch as low as 20mm or less in thickness shows minimal cupping and remains “as flat as a board” forever. It is very easy to lay as flooring, comes in tight even if slightly bowed and shows minimal shrinkage if seasoned to match the humidity of the site, as with all flooring. It shows no signs of “cell collapse”.Growing straight and stiff, it shows horizontal cracking from “reaction wood” like pine, kahikatea etc,
Absorbency:The wood is also highly absorbent allowing deep penetration of paints and hardeners, so that a very tough surface can be created. This property has been overlooked, but discovered in our experiments with finishing and hardening the timber. It sucks up oils, stains and resins “like a sponge”, unlike oily timbers and hardwoods, and therefore can be easily surface-hardened to great effect. However, all flooring except for the heaviest imported hardwoods will easily be dented by sharp objects, hard heels, hard furniture legs etc, and all exposed timber flooring must be treated with care. If you really want to abuse your flooring or need industrial uses, stick with matai, red beech and imported hardwoods and forget totara, rimu and kauri. For building, carving, sculpture, boat-building and all manufactures,it has ideal stability and fine finish.
Elasticity/stiffness: Totara is rated as low elasticity and therefore not as resistant to lateral forces as some structural timbers. However, there are reasons for this and some distinct advantages. It is a very fine-celled timber with tight growth rings (illustrated) giving it exceptional stiffness and stability which are great advantages for all woodcrafts and rigid panelling, flooring, posts, etc. It will not rip or tear like many other timbers, but extra care must be taken with splitting, including nailing too near the ends of a board or a Totara also has an unusual point of rupture under extreme loads, and generally will explode into 3 pieces rather than rip or tear like more elastic timbers. Unlike such timbers, totara loves a sharp chizel and will chip out cleanly leaving smooth cut surfaces and planes off cleanly and smoothly, with the exception of “rippled” feature where the plane crosses the grain and furring occurs; but this is easily solved by fine sanding,filling and hardening with resins or varnish which soak deeply and permanently into any end-grain areas.
Structural strength:Being stiff and light, totara is not as structurally strong or elastic as building timber such as radiata pine. Although stable and stiff, it can shatter under excessive loads, typically into 3 pieces! It is ideally suitable as posts, joinery, visible frames and trims, furniture, etc, but if used as structural beams or studs I would use 15% larger dimensions to bring the relative Modulus of Rupture up from 62 to 73, similar to macrocarpa, lusitanica, etc, but engineer’s advice should be obtained for consent purposes; i.e. use an 8×2 where a 6×2 would pass; or simply use closer support spacings. It does make magnificent beams and has been widely used in the past, either roughsawn or dressed and polished, but caution is advised. For concealed or enclosed structures, other timbers are much more suitable and cheap.For increased solidity and to avoid closer joist spacings, we specialise in extra thick flooring and can produce to order.
Marine uses: Totara has exceptional marine uses, being light, workable, easily steam-bent, durable below and above water, and one of the few timbers which resist toledo woodworm as well as all other insect and fungal damage. It is ideal for structures, hull planks and decking, except for heavy industrial wear where teak is unsurpassed. As described, it is a boat-builder’s dream: shapes easily, retains its shape without warping or bending, has exception gluing properties, nails and screws easily with minimal splitting, has structural stiffness and strength for posts (heavier beams advised), stability and low-shrinkage when dried, takes all the best modern finishes, oils and stains easily, looks and feels good.
Disclaimer:
In producing this advice, reasonable care has been taken regarding the accuracy of the information presented. However, no
guarantee as to the truth, accuracy or validity of any of the comments, implications, recommendations, findings or
conclusions are made by the author. Therefore, neither the author, nor any of the supporting organisations, shall be liable for, or accept any responsibility for, any loss, damage or liability incurred as a result of direct or indirect result of any reliance by any person upon information or opinions or recommendations expressed in this work. Users of any of this information, whether contained or inferred, in or arising
from this report do so at their own risk.
CLEAR SURFACE FINISHES FOR TOTARA
(See Disclaimer below).
History: As commercial supplies of totara declined, with kauri and rimu became the dominant native timbers, little research was done into the qualities and finishing of the timber, and the memory of difficulties in surface finishing and painting totara, due to the embedded resins, remained. The old method of applying oil-based paints and undercoats often resulted in defective and short-lived finishes, although the underlying timber survived unharmed under peeling or cracking paint. However, totara is not an “oily” timber as it is reputed, unlike some hardwoods which require special treatment. With drying or seasoning it is a very dry timber, the resins being embedded in hard form; it becomes oily only in contact with oil-based liquids including turpentine. With the revival of interest in it as a forest farm timber in Northland and our experimental work, it has now been shown that there are abundant paints, sealants and modern varnishes available to which totara is ideally suited.
OUR FINDINGS (see photo of sample board):
1. Traditional oil-based paints and polyurethane finishes: may still be used, provided that the timber is sealed with volatile solvent-based treatments such as diluted 2-pot epoxies and proprietary equivalents, including single-pot moisture-cured polyurethanes. It is also recommended (although we have not found it necessary with West Coast totara including sapwood) to wipe the bare surfaces with solvent such as Epoxy Solvent or common acetone in case of any surface bloom of resin crystals.This not only locks in the natural resins to stop them seeping out into ordinary finishes, but with one or more coats penetrates deeply into the cells and brings out the colour and tone of the timber in spectacular ways. A light sand over the sealant may be advised, depending on how set it is. A sample of this dual-coat is shown as the loft of Heartland Timbers’ warehouse loft floor.The advantage of final coats in turps/oil-based “pollies” is that UV protection can be achieved for flooring and outdoor timber exposed to direct sunlight.
2. Acrylic floor finishes: I have found that all water-based clear acrylic flooring finishes soak in and seal the timber without any sign of defects such as blistering, wrinkling, etc. Again, it may be preferable with denser heart boards or any with signs of resin bloom to wipe them off first with acetone. The effect is a much paler and softer appearance, starting as a pinkish tone, quickly softening to light straw tones with air exposure and multiple coats.
3. Moisture-cured polyurethanes: These are available in bulk and are the cheapest and quickest way to cover totara in bulk. After wiping off, this will soak deeply into the timber and may be recoated without sanding if not left too long. I have found that it may be layered on quite thickly in multiple coats before fully setting, but this needs some skill to avoid wrinkling or scuffing. Makers’ specifications should be followed as to sanding and cure times. I have also used this as a sealant, sanding first for top coats of oil-based polyurethanes, with no signs of lifting or reaction, but long-term durability is unknown. Moisture-cured is recommended for interior uses only. It is not UV-protectant, and it may be advisable to light-sand it and finish with UV-protectant oil-based polyurethane.
4. Epoxies and 2-pot varnishes. These are high-tech and more expensive and will also need UV protective finishes but are perhaps the most “bullet proof”, can be diluted up to 5:1 for maximum penetration and hardening, provide the ultimate depth of tone, hardness and durability. Using West System 5:1 Epoxy, I have found that totara sucks it up at any dilution, takes thickened adhesives and sawdust/powder mixes every time and can be combined in every way with mixes for filling, bonding and finishing to provide incredible integration, hardness and clarity. With experience, it can be recoated indefinitely to build up ultimate finishes and glassy effects, while still curing and sticky, without any intermediate sanding. Examples are shown in many images on this website.
5. Diluted epoxy: If the preference is for a deep mat finish for panelling etc, epoxy resin diluted with 1 part resin and 2 parts solvent (acetone or epoxy solvent) creates a unique “natural” finish, bringing out the deep purplish red tones of the timber. This is less dilute than the recommended first sealer coat for other finishes, and may left as a single coat only for suitable non-wearing uses. As a single coat it is completely mat and with two or more coats it becomes progressively glossy and slightly more golden. Colour changes are shown on the sample board above.
6. Natural oils: Totara takes all natural oils without problems, apart from occasional stickiness for some thicker oils. It is particularly good at taking stains and pgments in oil or flooring finishes. However, I have not found the finished effect as vibrant and durable as other finishes, or tried proprietary oil finishes for flooring as yet, but would expect them to be fine provided that the timber was wiped down first with acetone, as with oily hardwoods etc.
7. Stains and tints: Totara was always known for its affinity with oils and stains. However, experimenting with pigments in all clearing finishes, I have found that it also colourises beautifully and evenly to create every shade from ebony to whitewash for minimal extra cost. Happy to share these techniques with customers.
8. Undercoats and paints:.As with flooring finishes, totara will take any paint provided that it is wiped and sealed with volatile sealants such as thinned epoxy, etc. The only traditional primer which seemed to work for a few decades was the toxic red-lead primer. For that reason the old timers thought “nothing could be done with totara, except fence posts”! However, Alkyd undercoats such as Altex’s Multibond give excellent results even for marine uses, with no sign of deterioration or stickiness, good penetration, and excellent top-coating. Problem solved. For fully marine finishes of course, various 2-pot paints and primers are available for outstanding and durable results. For those of us who can’t bear to paint beautiful native timber (just buy tanalised pine) a full glass finish in epoxy with rather costly UV-protectant clear 2-pot overcoat will see us out, or even some elbow work on sanding and coasting with common oil-based clear marine finishes. However, the NZ sunshine will always win out eventually, and refinishing will probably be needed eventually on any natural timber, including the heaviest hardwood. The ultimate cure for ultraviolet damage is shade or cover – put a roof over it!
The above information and opinions are the result of ongoing research and experimentation, and are subject to the Disclaimer below.
Disclaimer:
In producing this advice, reasonable care has been taken regarding the accuracy of the information presented. However, no
guarantee as to the truth, accuracy or validity of any of the comments, implications, recommendations, findings or
conclusions are made by the author. Therefore, neither the author, nor any of the supporting organisations, shall be liable for, or accept any responsibility for, any loss, damage or liability incurred as a result of direct or indirect result of any reliance by any person upon information or opinions or recommendations expressed in this work. Users of any of this information, whether contained or inferred, in or arising from this report do so at their own risk.