The biggest threat during a zombie outbreak is, of course, the zombies. A close second is your neighbour (both literally and figuratively). It is very important that I keep that in mind.
If I make my home a fortress, and stock it with food, water, and weapons, and anybody notices this, I become the neighbourhood crackpot. During an outbreak, at best I look like a saviour, at worst a target; neither is desirable. I'm going to have provisions for my family, not yours. In other words, the Zeds are the Big Bad Wolf, and I'm the Little Pig who made his house out of bricks and mortar. The difference is, when the Wolf blows your house down, this Little Pig isn't unlocking his door to let you in.
It would be easy enough to prevent zombies from entering a fortified home. Preventing human entry takes it to a whole other level.
So, what does that mean for my current situation? Well, I live in a townhouse complex. My biggest fear is fire. Should any neighbour do something stupid, all my plans are shot to hell, with the exception of my escape plan (TBD).
As I live on a hill, at the foot of a mountain, the front door of my townhome is on one floor, but the back door is one floor down. My first order of business is securing the "basement", followed by the main floor, then isolating the upstairs from the down.
Basement: The door itself is sturdy and has multiple locks. It wouldn't take much to secure it further. The bathroom has a window, but it's about 6 feet up and only about a foot high. This wouldn't be hard to secure either. The weak link in the chain is definitely the "storage" room. It has sliding glass doors. I'll need to either replace those or fortify the room from within or outside. The door to that room opens outwards into the laundry area. That will need to be changed so it opens into the room and can be locked from outside. I think I'll replace all the basement doors with metal fire-rated doors. They won't splinter and can stand up to a decent pounding. (Remember, zombies don't have superhuman strength, they're only as strong as the body they occupy; they just don't feel pain or get tired.) Then again, living in a coastal city, I'm wondering if I could find some cheap bulkhead doors... like you'd find in a submarine. I'll have to look into those options and post the results later.
Main Floor: The front door is like the back door, but it has a slim window beside it. The kitchen has a window, too. Those are the only openings to the outside on that floor. (The living room, on a split-level, has sliding doors, but they open up to a balcony that's one floor above grade; and we all know zombies can't climb.) If I could replace the front windows with transparent aluminum, I'd do that, but since I can't time travel, I'll need to find another way to secure this area without compromising aesthetics (for the time being). Cost is unknown depending on the solution. (Est. <$200)
The next concern, would be the balcony off the living room. As I just mentioned, it's safe from the ground. What it's not safe from, however, is the neighbour's balcony. The dividing wall will need reinforcement. Not much, as it's pretty sturdy, but still, I don't want to risk anybody (even my neighbours) from doing an end-around. Cost is unknown depending on the solution. (Est. <$100)
Finally, there's the matter of isolating the upstairs from the rest of the place. I have a choice; I can either tear out the stairs and rebuild them so they can be removed in a hurry, or I can look into ways of just tearing them out when needed. Again, zombies can't climb very well, and a missing staircase could not be overcome. It wouldn't even need to be all of the stairs, just a few. A simple plank would be enough for us to bypass the hole, if and when things are clear. Cost is unknown depending on the solution. (Est. <$500)
Two of the bedrooms have attic access. In the months we've been living here, we've never bothered to look to see what kind of spaces are up there? Are they built to withstand people being up there? Storage? Or is this something I'll have to work on. Whether the attics are usable or not, they will eventually be used to store provisions.
I'll have to get some solar panels for backup power. In a Level 3 or 4 outbreak, we could lose power and water. A 200 watt solar panel will run just over between $1,300 and $1,500 plus tax. Add some batteries for storage and the hardware required to use that power (converting DC to AC), and you're looking at upwards of $3,500 for a couple panels. The good news is that if you hook that into the grid now, you'll get the benefit of net metering, which is when the utility company buys your unused power from you. It won't pay for itself overnight, but it would take the edge off... and it's a green thing to do. Another option, or addition, is that of a human dynamo machine. Or, in other words, a stationary bike hooked up to some batteries. A single adult could generate 125-200w of power. The upside is "free" power and exercise. The downside is more fuel (food) is required to run the engine (person). Unfortunately, most modern appliances tend to need about 1000w of power. A quick search on the internet shows that most "low wattage" appliances require 500-800w. Add a
solar cooker to the mix instead, and you won't need as much power.
As for water, that's only a matter of some piping, a clean surface to capture the rainwater, and something to store it in. You don't want to assume you'll get water during an outbreak. A waterbed mattress would do the trick, but you'd want to make sure the water is filtered and that wherever you put the mattress is strong enough to support the weight (like in the aforementioned attic). A king-sized free-flow bladder costs about $100, and the fill and drain kit is another $20. I'm sure I could get a granulated carbon filter, good for 6 months, for about $10. All told, I think I could get drinkable water for under $300 (I'd need 2 bladders. See below).
Each king-sized bladder holds about 790 liters. Normally, that would only be good for a about five days for my family (320 l/day) using both bladders. Under outbreak conditions, however, I
calculated that we could get by with substantially less (45 - 60 litres per day would be the comfort zone), and still not stink to high heaven. Given the annual precipitation of where I live, factor in a water catchment area of about 20 square meters (10 on the North slope of the roof, 10 on the South), and assume the bladders are kept filled during "peace time", we'd have enough water to live all year around. In fact, with the given data, we could use 68 l/day... assuming "average" conditions and regular maintenance.
The biggest potential roadblock to some of these is getting it approved by the strata council in our complex.
So, that takes care of power, water, and some protection (or at the very least, what I need to research further).
Next up? Food... ours, not us.