Sherwin-Williams acquires UK fire protection coatings firm Leighs Paints

07.07.2011

UK-based industrial fire protection coatings company Leighs Paints has been acquired by US-based paints major Sherwin-Williams. The acquisition significantly enhances the product portfolio of the company’s protective and marine business, the company said.

UK-based industrial fire protection coatings company Leighs Paints has been acquired by US-based paints major Sherwin-Williams. The acquisition significantly enhances the product portfolio of the company’s protective and marine business, the company said.
Terms of the deal were not disclosed.

Leighs Paints manufactures a comprehensive line of intumescent passive fire protection products for the hydrocarbon market. Its FIRETEX brand has been used on more than 400 projects around the world protecting offshore platforms, refineries and chemical plants, officials said.

“Leighs has a reputation for high quality products and expertise which will complement our current product line, making it possible to offer a comprehensive portfolio to our customers globally,” said Narsi Bodapati, vice president of marketing.

“The Leighs brand is an established leader in the protective & marine segments with a broad technology offering including intumescent fireproofing products and high performance protective coatings and linings.

The FIRETEX technology, consisting of epoxy intumescent coatings, helps achieve the fire resistance ratings necessary for a sound passive fire protection system. It is engineered to achieve this with a lower required film thickness than alternatives, Bodapati said.
Intumescent coatings react to fire by rapidly swelling, forming a thick char barrier that protects a steel substrate from structural failure.

With the acquisition, Sherwin-Williams gains a team of structural engineers who specialize in fire science and assist project owners and engineers with specification and compliance in this crucial area - another important asset, according to Bodapati.

“Leighs Paints, only a few years older than we are, has the same type of history, culture and customer focus that we have, which makes our companies coming together even more exciting,” he said.
The two companies combined have nearly three centuries of experience in coatings innovation, he added.

Sherwin-Williams Completes the Acquisition of Leighs Paints

http://www.leighspaints.com/en/News/SW_announcement.htm
On the 6th July 2011 the Sherwin-Williams Company acquired Leighs Paints.
The Sherwin-Williams Company is a global leader in the manufacture, development, distribution, and sale of coatings and related
products to professional, industrial, commercial and retail customers.
With 32,000 associates and $7.7 billion in sales, it is the USA's #1 paint and coatings company; #3 in the world.
Chris Connor, Chairman and CEO of the Sherwin-Williams Company, said,

“We are very pleased to bring Leighs Paints, a well-respected company, and
their employees into the Sherwin-Williams family. Combined, our two
companies have nearly three centuries of experience in coatings innovation.

This is another positive step in our strategy of steady growth and
expansion through quality products and people who provide excellent
customer service. This acquisition reaffirms our strategic commitment to
growing globally.”

Brian Leigh-Bramwell, Chairman of Leighs Paints, said,

“This outstanding
company has been a part of my family for the past 151 years. I am confident this decision will be of great benefit to both companies and our customers well into the future.”

George Heath, President of Sherwin-Williams Global Finishes Group, stated,

“This acquisition is another important step in our efforts
to strengthen our growing global platform. In joining our Protective &
Marine Coatings Division, Leighs Paints FIRETEX brand provides a new opportunity for us to better serve our customers around the world with outstanding technology, people, and assets.”

 http://www.leighspaints.com/en/Fire.aspx

World Trade Center slowly being "knitted back into the city"

By Douglas Quan, Postmedia News August 27, 2011
 
NEW YORK — Life, finally, has returned to "The Hole."
After lying dormant for years, the 16-acre World Trade Center site is teeming with cranes, earth movers and 3,000 construction workers daily.
Their job? To transform the site into a place that simultaneously memorializes and revitalizes — where people can come to quietly reflect and where capitalism can flourish.
Architect Nick Zigomanis, whose Toronto-based firm Adamson Associates has played a role in shepherding major parts of the complex project, says he's confident the right balance has been struck.
"We had to decide what is the new way we're going to live after all this? Are we going to solidify all this into a gravesite and memorial and stop moving? Or are we going to live?" he said.
"For me there is absolutely nothing wrong in saying this is a place to live and shop and make money and bring the business here. That's why we're all here. New York wouldn't be New York."
*****
In the immediate aftermath of 9/11, Zigomanis worried whether anyone ever wanted to build a skyscraper again.
Today, all he has to do is look out his office's windows at the World Trade Center site to get his answer.
Or rather, look up.
On the northwest corner of the site sits the partially constructed One World Trade Center tower which, when completed, will be the tallest building in the United States — a symbol of American resilience, some might say defiance.
In addition to the 1,776-foot-tall signature tower, the plans also call for three more office towers, retail stores and a major transportation hub.
Equally important, the site will provide space for people to get away from the hustle and bustle.
The centrepiece of the site is a memorial plaza filled with a forest of oak trees. The original footprints of the Twin Towers have been transformed into pools; water gently cascades down their walls, the names of each 9/11 victim inscribed in bronze around their borders.
There will also be an underground 9/11 museum and an above-ground pavilion, containing architectural elements from the original towers.
*****
Arriving at this balance between rebirth and remembrance did not come easily.
During early phases in the solicitation of ideas, some designers were adamant there should be no commercial development anywhere on the site.
Others took the opposite view. Don't just rebuild, but rebuild bigger and stronger, they said.
Contributing to the problem were the numerous parties who had a say in the redevelopment. The Port Authority of New York and New Jersey owns the site, developer Silverstein Properties is the major leaseholder, and the Lower Manhattan Development Corp. is a joint state-city corporation co-ordinating the effort.
Even after architect Daniel Libeskind's master site plan was chosen in 2003 following a worldwide competition, the reconstruction project faced further delays because of disagreements over the specific designs of each element of the site, which were parcelled out to several different architects.
A New York Times article in 2005 referred to the project as "one of the most muddled developments in the city's recent memory."
"It was very depressing to go by the site and read on a daily basis the incompetence of the powers involved. Everybody was fighting everybody else. Nothing was getting done," recalled Andrew Dolkart, director of the historic preservation program at Columbia University.
But now that the construction is well underway, it has helped to give a psychological boost to those who live and work in the area, he said. A site that was a "barren wasteland" for years is now slowly being "knitted back into the city."
The redevelopment also sends a clear message that New York is a "city that remembers but a city that goes on into the future."
******
New York City architecture firm Skidmore, Owings & Merrill and architect David Childs took the lead role in designing One World Trade Center.
From its cubic base, the 105-storey tower rises in the form of eight isosceles-triangle glass walls, and tapers at the top.
"A skyscraper of that height has to be an icon. One of the things that was important to us in the beginning was to create an icon, a building that's recognizable only by its shape," said Montreal native Donald Marmen, an associate director at the firm.
As for the detailing, the firm chose a type of glass that is very specular and that would reflect light. As the sun moves through the sky, the tower's surfaces shimmer like a kaleidoscope.
The other three towers, located along the site's eastern edge in descending height, each boast their own identities as well.
Designs for each were finalized over an intense period in the summer of 2006 with Zigomanis' firm, Adamson Associates, helping to oversee the process.
- Tower 2, designed by London-based firm Foster & Partners, comprises four mini-towers whose diamond-shaped tops are cut off at an angle, as if to point back at the memorial plaza below.
- Tower 3, designed by London-based Rogers Stirk Harbour & Partners, emphasizes transparency — showing the mechanical "guts" of the building.
- Tower 4, designed by Maki and Associates in Japan, takes on a minimalist approach with a cooler feel.
Sept. 11 really caused architects to think the "unthinkable" when incorporating safety features into their designs, Zigomanis said.
To that end, each tower was designed with additional options for getting out of the building, features to avoid a progressive collapse, better fireproofing and more emergency backup lighting.
*******
A billboard next to the site says the future has "never been brighter."
But traces of 9/11's dark days are never far. Street vendors peddle $5 booklets with graphic images of the planes barrelling into the Twin Towers.
A memorial wall outside a firehouse next to the site pays homage to the 343 firefighters killed that day. The pews at nearby St. Paul's Chapel still bear scuff marks from when 9/11 firefighters came to rest or pray.
A big question, however, remains: will people want to work here again? Dolkart, the Columbia University expert, admits he would not want an office in One World Trade Center.
"If there's any building in the world that's a target, that's it," he said.
"It has symbolic meaning for people who are troublesome. What more obvious target would there be than that?"
But there are some promising signs. In May, a news release announced publishing company Conde Nast would occupy one-third of the One World Trade Center tower, using the building as its headquarters and home for its magazines and websites.
Zigomanis says he gets his confidence from an encounter he had with a stranger a few years ago.
He and other project planners were heading to a meeting with technical drawings tucked underneath their arms.
They passed a group of tourists trying to sneak a peek through the perimeter fencing. A woman in the group, recognizing they were probably involved in the redevelopment, stopped them.
"Whatever you do, make sure this doesn't become a graveyard," she said.
"This is a place to live."
Dquan@postmedia.com

Exterior Painting Should Be Done Under Right Weather, Institute Says

Now that September is upon us, most of the country is entering the stretch run of the exterior painting season. If your house is in need of a new paint job, there’s little time to waste: “Paint-friendly” weather is fast disappearing.

“Doing exterior painting in the right weather conditions is extremely important,” says Debbie Zimmer, paint and color expert at the Paint Quality Institute. “Fresh paint forms a better protective film when it’s applied in moderate weather like that commonly seen in early autumn. If your house needs to be painted this year, you need to paint it now.”
To appreciate the urgency, it’s important to understand how paint “cures”. While latex paint dries to the touch very quickly, it actually takes many hours for it to form the most protective paint film. If the temperature is very hot when the paint is applied -- or more likely as winter approaches, if nighttime temperatures get very cold -- that can adversely affect film formation, and even lead to early flaking and peeling of the paint.
This point is vividly demonstrated on test panels at the Paint Quality Institute. More than 40 years of outdoor testing there shows that exterior paint applied in moderate conditions can last many years longer than paints applied in very hot, very cold, or even very windy weather.
Those extra years of service can offer homeowners a big return on their investment in an exterior paint job. As an example, let’s say a new paint job costs $3,000. If it lasts only five years, the annualized cost is $600; but if it holds up for 10 years, the annualized cost is only $300 – half as much!
As the days get shorter and winter approaches, painting in moderate weather is one of the most important factors in getting a long-lasting exterior paint job. Other things that can affect the longevity of a coating aren’t so time-sensitive, according to Zimmer.
“To get the most durable paint job, it’s always very important to properly prepare exterior surfaces and to use a top quality paint,” she says.
Good exterior surface preparation requires that siding and trim be clean and free of dust, dirt, and mildew, so that the new paint can adhere properly. Of course, peeling, flaking, or otherwise unstable paint should be completely removed, and any bare wood primed before painting.
As for the type of paint to use, studies show that high quality 100% acrylic latex paints are the most durable coatings for most home exteriors, including wood, masonry, vinyl and aluminum siding. These paints adhere well, they’re tough, and they’re very flexible, so they tend to expand or contract with the home exterior when temperatures rise or fall dramatically.
Which brings us back to the weather: As the song says, “For everything, there is a season.” When it comes to exterior painting, that season is now.

Written by Debbie Zimmer
Paint Quality Institute

San Jose fights graffiti surge

By John Woolfolk jwoolfolk@mercurynews.com Posted: 09/18/2011 03:14:12 PM PDT Updated: 09/18/2011 03:14:13 PM PDT

San Jose has seen a sharp spike in graffiti, up 38 percent from a year ago to the highest number of documented tags since 1999.

The surge comes at a time when budget cuts have forced the city to outsource its cleanup work.
City officials say annual surveys done each January since 1999 noted 44,405 graffiti tags citywide this year, up from 29,285 in January 2010. That was the highest figure since the city first started tracking graffiti tags in 1999 and counted 71,541. The City Council will consider the issue Tuesday.
"The volume of graffiti is higher," said Mike Will, a San Jose parks manager who oversees graffiti abatement, adding that reasons for the spike are a mystery. There hasn't been a greater number of any particular type of graffiti, he said.
"It's generally everything," Will said. "Maybe it's something to do with the economy, people's frustrations. We're still talking to experts and police to see what's going on."
Mario Maciel, superintendent of the mayor's gang task force, doesn't believe the surge is related to gang activity and blames "tagging crews" of high-school kids who thrive on the thrill of spreading their tags all over town.
"When there's a quantifiable spike, it's these tagging crews," Maciel said. "It's the whole notoriety among their subculture. That's how they validate themselves. We see that as a social epidemic."
San Jose saw sharp drops in graffiti from 2000 through 2003, and the number of reported tags generally held between 2,000 and 4,000 for the next several years. But in 2008 the number jumped to 13,902 and has risen dramatically each year since.
City officials in the latest January survey noted the sharpest one-year tagging increase in the city's fifth council district, centered in East San Jose, where the volume nearly tripled. District 7 in central San Jose also saw a substantial rise in graffiti. Downtown's District 3 as well as West San Jose's District 1 and the Cambrian area's District 9 also saw increases. Tagging volume dropped elsewhere.
Councilman Xavier Campos, who represents District 5, said he has noticed the surge in tagging and vowed in a statement Friday to devote city resources to fight it.
"Despite our budget cuts, we can not allow for the city's graffiti problems to spiral out of control," Campos said. "Under my watch, I will work to get to the bottom of what has caused the recent increases. The taxpayers expect better, and as council member of a district that is plagued with graffiti, I intend on making sure they get the benefit of every dollar they spend."
To close a $115 million budget deficit in June, San Jose officials outsourced the city's graffiti abatement program to a private contractor to save $1 million. Under a $633,000 contract with the city, Graffiti Protective Coatings Inc. is taking a somewhat different approach to cleaning up tags. By taking time to match paint to the vandalized surface, they are working to erase not only the tags but evidence that they've been painted over.
Will said that because the city had a limited variety of paint colors, its graffiti abatement crews could seldom match the original surface when painting over tags. Over time, he said, those surfaces began looking splotchy, giving them away as prime graffiti targets.
"You ended up with a quilt-patch of covered graffiti, which in many cases looks just as bad," Will said, noting that those surfaces were often quickly vandalized again.
Barry Steinhart, general manager of Graffiti Protective Coatings, said San Jose isn't alone in seeing a surge in graffiti.
"Everybody's increasing," Steinhart, whose Los Angeles-based company also has served Alameda County and the cities of Santa Cruz, Long Beach, Santa Ana and Mesa, Ariz. "Graffiti's a problem everywhere. It's like a sport to these kids."
Steinhart said he was surprised how much graffiti there was in San Jose but that his crews are working to paint over tagged areas so that they don't invite repeat vandalism and are easier to manage. The company's crews are starting in the hard-hit East San Jose area.
"They had a lot more graffiti than we anticipated," Steinhart said. "It's just going to take a little bit of time to get everything under control and where it needs to be."

Intumescent Paint and Coatings

Written by: Tarun Goel • Edited by: Lamar Stonecypher
Published Jul 14, 2011 • Related Guides: Sun Exposure

Spray-on fireproof coatings are an effective method for protecting equipment and structures from fire and heat. However, these materials tend to have particular advantages and disadvantages. Read this article to learn about the properties, indications and applications for these coatings.

An intumescent paint is a type of coating that is a fire retardant that also protects structural members from the ill effects of hot weather and sun exposure. It can be applied to wood, bricks, walls, and other structural members of a structure, to steel and plastic piping, and to fiberglass structures. These coatings are usually made of organic substances like epoxy resins and other thermosetting polymers that have high resistance to heat and fire.

How Intumescent Spray-On Fireproofing Works

Intumescent substances swell when exposed to heat and fire. When used as a paint coat or fireproofing spray, they form a protective layer on the surface. When exposed to fire or excessive heat, the protective layer will resist and absorb heat, thus protecting the structural member from damaged or deformation. Volume expansion and density reduction takes place when temperature starts to rise. Organic materials used for the manufacturing of intumescent paints are inert at low temperatures, but they swell instantaneously when brought into contact with heat or fire.

Intumescent paints are either solvent based or water based. In both cases, they contain a sufficient amount of hydrates to help in cooling off the temperature because of evaporation effects. Water based paints are used most often because they are inexpensive and widely available. Solvent based intumescent paints have, so far, seen only limited usage.

Another classification system, which takes into account the nature of the char produced by intumescent paint, is also in effect.

Soft char intumescent paints produce only a light char upon initial heat exposure. The char is a bad conductor of heat, and it does not allow the heat to pass through the paint coat and reach the structural member. It also contains hydrates which have a cooling effect. This is used primarily for the protection of structural steel.

Hard char intumescent paints produce hard char, which is also a very poor conductor of heat. These paints are exclusively used for plastic pipe protection. The major constituents of hard char are graphite and sodium silicate.

Advantages and Applications

1. Intumescent coatings prolong the structural life of steel. As protected steel is less exposed to frequent temperature variations, its load bearing capacity also increases.
2. The coatings can be applied off-site as well as on-location. Off-site fireproofing means there is enough time for workers to fit, erect, and adjust their structural components. Faster and easier construction, reduced on-site activities, and ease of assembly are the major advantages of off-site coating.
3. These specialized paints have a wide range of use. They can be used for steel coatings, wooden coats, or for structural components like concrete as well. Recently intumescent fireproofing sprays have been developed that can be applied to fiber glass structural components, too.
4. Advantageous use of these products can be made in refurbishment projects. The structural, aesthetic, and architectural value of the structural objects remains preserved.

As already stated, intumescent paints have a huge scope of use. These paints are mainly used in fire-stopping, closures, and fireproofing works in buildings, houses, and manufacturing industries. Gasketing applications also make use of intumescent spray-on fireproofing paints. Major use of these paints is found in offshore drilling, aircraft maintenance, and the ship building industries.

Disadvantages

The intumescent fireproofing industry is on the rise and has already created a stir in the market. However, there are certain drawbacks associated with these paints.

• UV exposure, operational heat, and the humidity of the work area are three major factors that affect the performance of intumescents. Intumescents are particularly vulnerable to environmental exposure at the time of application.
• For sodium silicate based intumescent fire sprays, having rubber or epoxy in the coatings becomes mandatory in order to promote adherence.
• They have a limited fire resistance period. The best quality, i.e. most expensive, intumescent fire sprays will not preserve your structural member for more than sixty minutes or so. As the fire resistance time duration increases, the costs also increases, and the cost rise is usually exponential.

Alternatives to the Intumescent spray-on paints are also available in the market.

1. Flexible blanket systems - Good - cheap, easy to use, dry fixing methods; bad - poor appearance.
2. Other fireproofing sprays - Good - covers complex details, low cost, durable; bad - on site application means more on-site headaches.
3. Board systems - Good - clean appearance, dry fixing, can be used on unpainted steelwork; bad - does not cover complex areas.

References

Author's own experience
Intumescent Coatings, Steelconstruction.org (pdf)
Envirograf, Fire Protection Coatings, http://www.envirograf.com/acrobat/coatings.pdf
Site Applied Protection Materials, http://www.civl.port.ac.uk/britishsteel/media/Fire%20brochure/section4.htm

Read more: http://www.brighthub.com/engineering/civil/articles/121361.aspx

Go green by painting your building roof white

Sandeep Ashar, TNN Jul 25, 2011, 04.10am IST

MUMBAI: The state government wants to promote 'cool roofs' to conserve energy.
A 'cool roof' is one treated with a coating to reduce the amount of absorbed solar radiation and heat. In general, these coatings are white or light-coloured. The term is also used to describe roof tiles that show similar properties. Research suggests that such roofs are more reflective that the conventional ones.
Conventional roofs (dark-coloured roofs) absorb heat instead of reflecting it. This raises the temperature of the roof during hot weather. The heat is also transmitted to the living quarters below, forcing many to switch on air conditioners.
By reflecting heat, a cool roof significantly minimizes such heat transfer, leading to savings on your AC bill. This, in turn, reduces carbon emissions and helps in promoting a cooler and a greener planet.
The state environment department has tied up with Dr Jayant Sathaye, a director with the International Energy Group of the renowned California-based and renowned Lawrence Berkeley National Laboratory. that has published research papers.
Valsa Nair Singh, secretary, environment department, said, "Models used in Delhi and Hyderabad, where the concept has already been introduced, are being examined." In Delhi, the government has modified building norms to make "cool roofs" a mandatory norm in new buildings. On completion of the ongoing study, the state urban development (UD) department could be asked to check the feasibility of similarly introducing similar changes in development control norms.
To promote the concept, Delhi first introduced the concept in government buildings. The US was the first to endorse the concept. With President Barack Obama advocating it strongly, the concept has gained tremendous ground within the States and is now trending in other developed and developing countries. Rebates in taxes were offered to popularize the concept in some parts of the US.
To bring down carbon emissions and slow down global warming effects, the state has been promoting use of green and environment-friendly building construction materials. Interestingly, the California research laboratory had also suggested use of light-coloured pavement tiles to reduce carbon emissions. However, state officials said that this was not being considered at this stage.

Water Storage Tank Design is Just a Click Away with Online Tank3D Tool from Tnemec

Tnemec Co., Inc.
6800 Corporate Dr.
Kansas City, MO, 64120, USA

Press release date: July 22, 2011

One of the most advanced interactive tools that allows users to customize elevated and ground potable water storage tanks with a wide palette of colors, graphics, text and even logos is now available from Tnemec at http://www.tnemec.com/tank3D. "With Tnemec's Tank3D, it is possible to visualize how a water tank will appear using variable design elements and Tnemec coatings," explained Doug Hansen, director, Water Tank Market. "Using this technology, more than 100 color options and countless graphic enhancements can be explored in minutes rather than hours or days."

With more than 40 years of experience as a manufacturer of protective coating systems for the water tank market, Tnemec has actively encouraged aesthetic, creative and innovative tank designs through the sponsorship of its annual Tank of the Year competition. "Most water tanks today incorporate graphic designs, such as the name of the town, or a logo or mascot," Hansen acknowledged. "With the development and introduction of Tank3D technology, we are making it even easier for tank owners, engineers, fabricators and painting contractors to use Tnemec coating systems in designing water tanks that are a source of community pride."

In addition to its color selection and graphic functionality, Tnemec Tank3D offers users the ability to zoom and pan around their customized tank, as well as view a pre-programmed "fly-by" that shows the tank from different perspectives. Printer-friendly PDFs and color swatches are also available using the new technology.

"This is the first truly interactive tool of its kind that offers such a wide range of functionality," according to Jessi Bixler, electronic marketing manager, who directed the creation and development of Tnemec Tank3D. "Existing applications for this market are little more than color guides with very minimal functionality."

The program operates on all Web browsers, including Firefox, Internet Explorer, Safari and Chrome, and is both Mac and PC compatible, Bixler explained. "The technology is activated by downloading a plug-in, which usually takes just a few seconds," she observed. "The user can then select their style of tank, the colors they want to use, along with text, logos and other graphics, so the final design will closely resemble the actual finished project. By varying the color, engineers and architects can determine which colors work best with other design elements such as logos and lettering."

Tank3D was introduced at this year's AWWA Annual Conference and Exposition in Washington, D.C., where it attracted immediate interest among attendees. "During our live demos, everyone was impressed with how quick and easy the program was to use, along with the fact that it allowed them to customize their design with logos and text using different typefaces," Bixler noted.

Tnemec coating consultants will be introducing their customers to Tank3D and its design features over the next several months. "The program is out there for people to use and experiment with and we encourage them to use it," Bixler added. Tnemec will continue to make enhancements to the tool for even more design options, such as new tank styles and different backgrounds.

Guesstamating vs. Estimating

Let's say you go out to a job and there's 100 feet of wall 9 feet high that needs to be primed and painted 2 coats. You look at the wall and figure that will take about a day to do. You go out to another job and there's 120 feet of wall 9 feet high that needs to be primed and painted 2 coats. You look at the wall and figure that it will take about a day to finish it. Guess what, you're guesstimating!
If you really want to make money consistently on each and every one of your jobs you need to estimate your jobs, not guesstimate them. Accurate estimating is crucial to your long term financial health.
Let me tell you how paint estimating should be done if you want to make money. Everything you do needs to be measurable for labor, materials and equipment. How do you do that?
Using our wall as an example, we need to find out how many squre feet of wall can be painted one coat in an hour. Let's say you know from experience it takes an hour per 300 sf to apply a coat of paint. So, for the 100 foot wall, 9 feet tall, you need to bid 3 hours per coat, or 9 hours toal, plus 3 gals of paint. For the 120 foot wall you need to bid 3.6 hours per coat, or 10.8 hours total, plus 4 gals of paint.  When you're guesstimating, which way too many contractors do, you're frequently either leaving money on the table or over bidding and not getting the job. Most of the time money is left on the table because you're eager to get the job.
Estimating is not a perfect science, but it beats the heck out of guesstimating. You may be asking yourself "how do I really know that I'm using the right standards for my estimating?" How do you know for sure that it takes 1 hour per 300 sf of wall per coat?

Estimating and Job Cost - the Secret to Making Money

In order to be confident in estimating, you need to measure your results. That's the only way to be sure that your estimating correctly is to measure your results. In the wall example above, let's say it only took 8 hours to paint the wall. You probably would modify your time for future estimates from 300 sf per hour to 338 sf per hour per coat.
That's how you make money consistently from job to job to job. Do everything in measurable units, measure the results and adjust your estimating for future projects.