What is Knob and Tube Wiring

Knob and tube wiring was a system of open electrical conductors supported on ceramic knobs. It also used ceramic knobs where wires cross each other or pass through framing. This type of wiring was in common use from the 1880’s to 1930’s, in North America. When working with wiring, electrician Brisbane 24 hours always cut the power supply at the breaker box first before beginning any actual work.

During the era when knob and tube was in common use, a typical home would have 30 or 60 amp electrical service, sufficient for general lighting and maybe a radio. These were the days of “iceboxes”, wood or gas stoves, coal heat, and no air conditioning. Wiring homes was a new trade, with very few rules.

The first home wiring rules appeared around the turn of the century, when Terrell Croft wrote the American Electricians Handbook. Crofts books defined early wiring practices. One of Croft’s rules was that knob and tube wiring should always be run through, never over the house framing. The problem with running wiring over framing is that it can get bumped, snagged, and damaged. Most electrical experts would agree that wiring run over the framing is a sign of amateur, cobbled-together work, and it never conformed to any electrical code.

Good Points

The theoretical advantage of knob and tube wiring is that it dissipates heat into free air, and therefore has a higher ampacity than cable systems with equivalent wire size. When originally installed in the 1900’s knob and tube wiring was less expensive than other wiring methods. Due to the installation cost, owners and electricians would opt for knob and tube versus conduit wiring and metal junction boxes. The conduit methods were known to be of better quality, but their cost was significantly higher than knob and tube wiring.

Modern wiring methods assume two or more load carrying conductors will lie against each other, for instance the standard non-metallic – 2 cable. Since the load carrying wires are in close proximity, when they heat up, the heating is shared across the wires, limiting the overall current load they can support. Since the load carrying wires in knob and tube wiring are widely spaced, the wires are capable of carrying higher loads without risk of fire.

Bad Points

Knob and tube wiring was commonly insulated with cotton cloth and soft rubber, in addition to the porcelain insulators. Although the actual wire covering may have degraded over the decades, the porcelain insulators have a very long lifespan and will keep any bare wires safely insulated. These same porcelain insulators are commonly used with bare wire electric fencing for livestock. These insulators can carry very high voltage surges without the risk of shorting to ground. Many electricians understand that by running the hot and neutral conductors farther apart from each other than today’s electrical cabling does make shorts between those conductors less likely, at the same time realizing there is not a grounding conductor.

Wiring installation standards and methods were less stringent in the era of knob and tube versus modern day electrical codes and standards. The main shortcomings of knob and tube include the following: lack of a safety grounding conductor, inability to confine switching to the hot conductor, the permitted use of in-line splices in walls without a junction box. Compared to modern thermoplastic wiring insulation, typically known as “romex”, the knob and tube wiring is less resistant to damage.

Knob and tube wiring is very vulnerable to mechanical damage, such as from stored materials in the attic or basement. Bending the wire can cause older insulation to crumble and fall off the wires.

Knob and tube is insufficient for current usage patterns. Contemporary households use a wide range and intensity of electrical equipment that was unforeseen at the time of knob and tube inception. Household power use increased following World War II, first generation wiring systems became susceptible to abuse by homeowners, who would avoid repeated blown fuses by overfusing the circuits, thus subjecting the wiring to heat damage due to higher levels of current.

In many instances deterioration and abuse have rendered the wiring unsafe. During building renovations and remodeling wiring can become damaged. The rubber insulation will become dried out, brittle when handled, damage by rodent, or simple carelessness – for example hanging objects off wiring in accessible places like attics and basements.

Covering knob and tube wiring with thermal insulation is unsafe and prohibited. This is a known fire hazard and it is specifically condemned in the National Electrical Code, Section 324-4. No form of insulation – loose, blown-in, or expanding foam insulation can be placed over the wiring. Knob and tube wiring was designed to let heat dissipate to the surrounding air. As a result, energy efficiency upgrades that involve insulating previously uninsulated walls usually also require replacement of the wiring in affected homes.

Homeowners insurance underwriters may refuse and deny coverage for homes and buildings that have this type of wiring installed.

Alan Trauger is a Building Consultant that performs property condition assessments for residential and commercial properties. An experienced and knowledgeable problem solver, understanding processes and issues related to building structures and their systems. An expert witness, trainer, and educator. To view past newsletters on construction and buildings [http://newsletters.alantrauger.com/]

To review authors bio, qualifications, and interest in receiving future email newsletters http://www.alantrauger.com

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The Organic Way To Search Engine Optimize Your Site

Google is one of the top players in the world and with your business all you need is to get a freelance SEO consultant Sydney. If your website lacks optimization for Google searches (or Yahoo! or Bing, for that matter), you aren’t maximizing your potential.

When setting up pages using SEO, it is better to use several short articles pertaining to a similar topic instead of one very long article. Long pages get weighted less weight than short ones.

Keyword density is vital when you optimize a web page for various search engines.To avoid this from happening, try to keep your total keyword content to under twenty percent of any given page.

Try to include a transcript for videos or audio content on your site.

This particular tag should not be more than 30 words. This page should be smaller than 100 KB.

Research information about keywords first so you begin. Learn which keywords will be best for you build your website. Keyword research can let you know what people use to navigate in your categories.

A site map which has your keywords. Site maps are great ways for search engine optimization.

It is important to constantly release new content and publish fresh articles.Websites that produce fresh content receive higher marks from search engines than those who barely update their sites. Sites with more new content will earn a higher search engine rankings.

Use videos and a video sitemap for increasing your website. You can make use of videos to familiarize your visitors with your staff and with your product.Post such videos on your site with good keywords. Once that is done, you want to use the webmaster tools available on Google to submit your site URL. This should glean you plenty of new customers.

Invest in advertising online advertising. DIY SEO might not always produce the jump in rankings you want.Advertisers will help you get more visitors. Using Google’s product by Google can help your website out a lot.

Captions are a tremendous SEO process.This means that sites with a great deal of photos or newspaper articles linked can use this to their advantage, you should use this as an opportunity to use some captions that have a bunch of keywords.

The title tag should be one of your site can benefit from significantly. This is the first thing visitors see when visiting your site. It should a good description of the website and have related keywords.

Once this thought has settled in, you can boost your business output by improving them. Don’t stop trying to get more people can see it.

You can use Javascript in your pages, but certain search engine bots don’t react well to it. Using Java is a choice that each website owner must consider; however, but some search engines see the site differently because of the capabilities of the various search engine spiders.

You can get free publicity that will help bring visitors with this service. Always take advantage of free advertising venue.

You won’t find many image links with sites that are optimized websites. Image links only provide the search engines effectively.

The keywords in your title tags have more weight with search engines than anything else on a page.

Don’t allow the domain registration information to be blocked. Google may see this as a spammer and remove your website.

If you have a shared server, you need to make sure that a banned site doesn’t share the same proxy. Sharing a server with a bad website will lower your rating, and thus not get you the traffic you desire.

Use definite commands that result in relevant results.

Focus on keyword phrases and not just the keywords with your SEO techniques.How often can you ever search by just using a single word? You need to choose phrases that guide customers to your site who are looking for the exact thing you offer.” instead of “We are going to have a sale! This is the quality of your keyword phrases properly.

Make sure to configure your server is configured to be case sensitive to capitalized letters on URLs.

Google Analytics is a must have. It can track your progress and better your results. You can find the most popular search terms that led customers to your site.This information will allow you modify your keywords down to the most searched for information.

Leaving posts on blogs that are compatible to yours may allow you gain links to your website. If you deliver a well-written and appropriate piece of writing, most blog owners will allow you to leave your link in the comment. You should make sure you leave links that are on relevant sites and not places where your links don’t apply because you want to add something to a site, and the comments you leave should add something of value to the other site.You can easily leave related comments and links to your site if you have a thorough mastery of your subject matter.

You can and should include Really Simple Syndication (RSS) feeds that relate directly to the content contained on your website. Regular updates to your RSS feeds show up as new content. If you are unable to find a quality feed to incorporate to your site, start your own where you post things related to your site. Make sure that you have people to follow your RSS feed as well.

Look to your placement in search results to see how your SEO is doing. Clear your cache before you check the position.

Use these tips to keep your site on people’s minds. Your search engine ranking will depend on the relevance assigned to your site. Employ these easy tips to get a good start today. Your competitors will use these strategies even if you don’t.