Work with homeowners to determine their present and future technology needs and design a system that's right for them
No two home technology projects are alike. No matter how similar two houses look from the outside, the specific requirements of the homeowners can be drastically different. Taking the time to sit down with your clients to determine what they need will not only ensure that they get what they want, but also prevent you from having to do things twice.
The last few articles in this series have dealt with specific home automation and structured wiring technologies and installation practices. This article, the eighth installment in a 12-part series that will prepare electrical contractors to take the test to be certified as home technology integrators (HTI), looks at the development of the project plan and the integration of many dissimilar technologies. The project plan, which is dictated by the customer's present and future needs and lifestyle, requires you to tap into your creative side.
Scope of project.
The first step in this phase of the project is determining the homeowner's current needs, establishing future technology needs, and setting the budget that you'll have to work with. Let's first focus on the homeowner's needs.
As the HTI, you must determine your customers' expectations for the system. Based on this response, you'll know what subsystems need to be integrated into the overall system. Tailor your customer interview and presentation according to the type of project (retrofit vs. new construction). Many homeowners don't know what's possible, so use the following list to help them determine their needs.
Which services do they want? Video, e-mail, Internet, security, or pool control?
Do they want to share devices like printers, files, scanners, CD-ROMs, and DVDs?
Do they want to be able to move equipment around? If so, a wireless option may work the best for them.
Do they have a home business or do they telecommute?
How many people live in the house?
Is security a concern?
Do they need to control or protect children's access to the Internet?
A first-time or technologically shy user requires a user-friendly interface and may need customer support material. Assess the technical competency of the homeowner beforehand so you can tailor the interfaces and instructions specifically for them.
Now that you have a clear understanding of the homeowner's needs, it's time to broach the subject of the all-important budget. However, in many cases you may find that these two items don't match as closely as you might like.
A home computer network can cost anywhere from $1,000 to $10,000, depending on its scope. The total installation cost depends on, among other items, the customer's geographic location and the amount of existing equipment that can be put to good use.
For example, a computer network for a home located in Silicon Valley with three to four PCs, a shared printer, and an Internet connection would cost the homeowner on average $5,000 ($3,000 labor and $2,000 for hardware and wiring). This estimate includes 5 hr to 8 hr of installation time and 2 hr of follow-up and fine-tuning scheduled about two days after the initial installation. In some cases, you may need to make another 2-hr follow-up service call about two weeks after the initial installation. This estimate doesn't include the installation or hardware for any of the other subsystems. What's important to note is that this cost will vary by location, type of equipment installed, and type of advanced technologies requested and included in the project.
Once the customer's needs and budgetary constraints are established, you can then begin your site survey and pinpoint the location of existing and proposed equipment. This includes determining the demarcation points, locating outlets, identifying power requirements, and selecting cable types.
Site survey and equipment layout.
In this stage of the design, you'll need to focus on general and specific issues for the project site survey. This information includes the type of construction (new, remodel, retrofit, single/multi-story or single/multi-family dwelling), the current environment (existing equipment, systems, and their location), and location of the home (rural, suburban, urban, the presence of tall trees, or surrounding hills). You should also make note of the type of materials used to construct the home (wood, stone, stucco), the number of stories and rooms (including basement and attic), the demarcation point locations, and the number and location of existing outlets in the home.
Locate demarcation points.
The demarc is the point where the service provider network meets the internal home. The location is normally established by the provider. The telephone company's demarc is often called a network interface device (NID). This device provides a quick means to connect and disconnect from the telephone circuit for testing and troubleshooting. It also provides lightning protection by means of gas tube elements that, unlike fuses, short to ground in the event of a lightning strike.
The cable television company's demarc, or ground block, looks like a splitter, but it has a ground lug on the housing. A ground wire runs from the ground block to the building ground. A coax ‘F’ connector is used at each end of the ground block. The cable company may also install filters that restrict premium services access at these locations. Cable companies may also install what they call high-pass filters at the ground block. These prevent noise or unwanted RF signals generated within the home from entering the cable television system. Since these filters block all return signals, they must be removed when using two-way services like digital cable or cable modem service.
Identify outlet locations.
Identifying the outlet locations in the home network is another step in the planning process. The homeowner's requirements are the most important determining factor in this step of the process. By carefully selecting outlet locations, you can limit the length and exposure of equipment cords. Although most outlets will be mounted about 15 in. above the floor, you may be required to mount some outlets higher. Wall phones are often mounted 5 ft above the floor, and home theater speakers and surveillance cameras are installed in the ceiling.
Determine number of outlets.
Once the outlet locations are determined, it's time to count them. The number of cable runs terminated in the structured media center (SMC) typically determines the size of the SMC. Since it takes about the same amount of time to pull a cable to an outlet, regardless of the type of service or type of cable involved, determining the number of outlets gives a good estimation of the total time it will take to complete the rough-in phase.
Identify power requirements.
Now it's time for you to identify which equipment will be network powered and which will be powered by standard outlets. You should locate video outlets near the power outlet that serves the television. Wireless phones require house power, so telephone outlets for these devices should be located near a power outlet.
Computing equipment like cable modems, DSL modems, hubs, switches and gateways, which won't be located in the SMC, will also require power. Computing devices are often powered by point-of-use surge protection devices, which require the availability of a standard house power outlet as well.
Never mount communications outlets on the same stud or in the same stud cavity as AC outlets. Plan to mount these outlets 16 in. away from AC outlets.
Determine applications served by outlets.
You should assign some type of application to each outlet. For example, some may be defined as “future use.” An EIA/TIA Grade 1 (or Level 1) installation will have one Cat. 3 or Cat. 5 cable and a single coax cable run to it. A Grade 2 (or Level 2) installation will be fed by two Cat. 5 cables and two coax cables.
Most installations will be a combination of Grade 1 and Grade 2. For example, the children's bedrooms may typically have a Grade 1 outlet, while the master bedroom may have a Grade 2 outlet and a Grade 1 outlet. The kitchen may have a Grade 1 outlet or even Grade 2 — depending on the homeowner's requirements — while the home office may have two Grade 2 outlets.
Entertainment centers may have two or more Grade 2 outlets, plus outlets for specialty cables for things like speakers. Sound systems may require a Cat. 5 cable for volume control and speaker wire for the actual speakers. Some internal video systems will require a coax cable and a Cat. 5 cable. The coax will deliver the video signal and the Cat. 5 will carry low-voltage power to the camera.
Determine cable type servicing outlets.
Once you've clearly defined the outlet applications, you can now determine the type and length of cable required for each outlet. Once the cable type and quantity per outlet is assigned, you can calculate the actual quantities of each cable type required for the project. Using the blueprints, determine the distances from the SMC to each outlet. Now tally up the amount of each cable type that will be required. Remember, longer cable runs may require the use of higher gauge wire.
Applications affect cable types.
The type of cable used for an installation is dependant upon the type of application required. Space can be limited, and newer composite cables that combine two Cat. 5 cables and two coax in a single jacket allow for a single cable pull. Sometimes it may be necessary to go outside of the house to reach a particular room. In this instance, outside plant-rated cables should be used, even for shorter runs. High-end video and audio applications can often make use of fiber optics. Fiber optics can also be useful when planning for future upgrades.
It's recommended that you run at least two Cat. 5 cables from the SMC to the telephone company's NID in two separate sheaths. Two 4-pair cables can support eight incoming telephone lines.
Most cable systems use a single coax to provide cable TV services to the home. Some cable companies use a separate coax for the cable modem to the computer and the television. Running two coax cables from the SMC to the cable TV's ground block provides redundancy and ensures that the system can support future services.
Structured media center.
By installing the SMC in a central location, you can minimize the length of each cable run. Avoid using the garage unless it's possible to build an enclosure within the space and the homeowner lives in an area of the country that doesn't experience severe temperature swings.
When checking the distances of your coax runs remember that the strength of the video signal delivered by the cable company will diminish as the cable length increases. Therefore, you may be required to install RF amplifiers to boost the signal. Since many services like cable modem and digital television are two-way, always use an amplifier that will work on the return path as well as the forward path.
There are other services that may be distance-sensitive, too. In fact, if the distance is too great, some may not work at all. Services like S-video, Firewire, and universal serial bus (USB) won't work beyond the 100-m mark, as defined by the EIA/TIA.
You should size the SMC based on three factors: the number of cables to be terminated in the unit, the types of cables to be terminated, and the number and type of active devices planned for the SMC. Since the SMC fits between studs, it will be about 14.5 in. wide and vary in length from 14 in. to 36 in.
You can install hubs, switches, gateways, and even cable or DSL modems in the SMC, as well as video devices like amplifiers, modulators, notch filters, and video switchers. On larger projects, you may need to install two or more SMCs. If this is the case, it's best to separate systems by application or type of device.
Almost all SMCs come equipped with a single gang duplex outlet. You should connect this outlet to a non-switched circuit with at least a 15A breaker. Many devices in the system operate at 12VDC. Therefore, the duplex AC outlet may be augmented with a power strip if additional outlets are required to serve various AC/DC transformers within the SMC. Some manufacturers of SMC units have developed 12V power supplies that can power multiple devices from a single power supply unit.
Costs and timelines.
Proper planning will help ensure that the project budget is proportionally allocated according to each phase of the project. You must carefully develop a comprehensive bill of materials, identify all labor costs, and coordinate with other trades well before you begin the actual installation. Budget mismanagement will affect not only the cost of the project, but also the overall satisfaction of the homeowner.
In new construction, both the rough-in and finish phases require careful coordination with the building contractor.
The proposal and contract.
The proposal is a document that outlines all of the work you plan to perform for the homeowner. This document should be presented in a clean and organized format and include only the key points of the proposal. Be sure to focus on benefits that you and your design have to offer. You may include information like the purpose of the project, your implementation plans, and your design strategy. Summarize your conclusion as a result of identifying the homeowner's needs.
After the homeowner has approved your proposal, you'll need to draw up a contract. It should clearly state the legally binding expectations and responsibilities of the parties involved. Rely on your normal business practices when preparing this document.
Although they can be modified, home networks are an expensive undertaking. Impress upon your customer the importance of planning for the future, and thoroughly research their needs before going ahead with the project.
Dusthimer is publisher of Cisco Learning Institute Press, York, Pa.