Key Takeaways
- Bleach removes mold's visible stain but does not eliminate the underlying root structure on porous surfaces.
- Dark paint colors can make a room feel cozy or dramatic — not necessarily smaller — depending on lighting and furniture.
- Many common renovations do not return their full cost at resale; understanding actual ROI prevents overspending.
- Pouring grease down a drain with hot water still causes buildup and blockages over time.
- Permits and inspections exist to protect homeowners — skipping them can create legal and safety problems.
Why Home Improvement Myths Persist
Home improvement advice travels fast — through neighborhood conversations, social media clips, and well-meaning family members. The problem is that some of the most widely repeated tips are either outdated, oversimplified, or simply wrong. Acting on them can mean wasted weekends, unnecessary expenses, or repairs that create new problems. The Home Maintenance hub covers the fundamentals that help prevent these kinds of costly missteps.
The myths below are particularly common and particularly consequential. Each one involves a belief that sounds reasonable on the surface — which is exactly why it keeps circulating.
The Myths, Corrected
Work through each of these carefully. Some may confirm what you already suspected; others might surprise you.
Myth
Bleach kills mold permanently, so spraying it on a moldy surface solves the problem.
Fact
Bleach eliminates surface staining on non-porous materials but does not penetrate porous surfaces to destroy mold's root structure (mycelium), and it does nothing to address the moisture causing the growth.
Bleach is effective on glass, tile, and sealed countertops because it can reach the mold fully. On drywall, wood, and grout, however, the water in bleach solution absorbs into the material while the active ingredient stays near the surface. The mold's hyphae — the thread-like structures that anchor it — remain intact and regrow quickly.
More importantly, mold is a symptom of excess moisture. Without fixing the source — whether that's a slow leak, poor ventilation, or condensation — mold will return regardless of the cleaning agent used. See our guide on bathroom ventilation for practical steps to reduce moisture at its source.
Myth
Dark paint colors make a room feel noticeably smaller and should be avoided in tight spaces.
Fact
Color perception is heavily influenced by lighting, sheen level, and how consistently a color is applied. Dark hues used thoughtfully can make a space feel intimate and well-defined rather than cramped.
The "dark equals small" rule is an oversimplification. When a single deep color is applied to all four walls and the ceiling — a technique sometimes called an "enveloping" paint scheme — the boundaries of the room become less defined, which can actually create a sense of depth. High-gloss finishes reflect more light and further counteract a closing-in effect.
Lighting plays a larger role than paint color in perceived room size. A dark room with good natural light and well-placed lamps can feel far more open than a white room with a single overhead bulb. Consider the full picture before ruling out a color.
Myth
Renovating your kitchen or bathroom will always recoup most of its cost when you sell.
Fact
According to widely referenced industry data, even well-executed kitchen and bathroom remodels typically recoup only a portion of their cost at resale — often between 60% and 80%, varying significantly by market and scope.
The idea that every dollar spent on renovation comes back at sale is a persistent and expensive myth. High-end finishes in a mid-range neighborhood, or over-improving relative to nearby homes, often yields returns well below the project cost. Our article on what ROI really means for home renovations explains how to think about value more realistically.
This doesn't mean renovations are a bad idea — improved livability and enjoyment have real value. But making financial decisions based on the assumption you'll "get it all back" can lead to overspending. Focus on projects that fix functional problems or improve energy efficiency, which tend to hold their value more reliably.
Myth
Pouring grease down the drain with hot water washes it away safely.
Fact
Hot water keeps grease liquid only temporarily. As the mixture cools in your pipes, the grease solidifies and accumulates, eventually causing blockages.
Grease, fats, and oils are among the leading causes of residential drain clogs and municipal sewer blockages. Hot water delays the problem — it does not eliminate it. Over time, even small amounts of grease coat the interior walls of pipes, narrowing the passage and trapping food particles, leading to slow drains and eventually full blockages.
The correct approach is to let grease cool and solidify in the pan, then scrape it into a sealed container and dispose of it with your regular trash. For larger quantities — such as after holiday cooking — many municipalities have grease recycling drop-off points.
Myth
You don't need a permit for small interior projects — permits are only required for major additions.
Fact
Permit requirements vary by jurisdiction, but many localities require permits for work involving electrical wiring, plumbing changes, structural modifications, and HVAC alterations — regardless of project size.
"Small" is not a defined category in building codes. A homeowner who adds a single electrical outlet without a permit may be doing work that requires inspection under local code. The same applies to moving a wall — even a non-load-bearing one — if it involves rerouting wiring or plumbing.
Unpermitted work creates real risks: it may not meet safety standards, it complicates home sales, and it can void homeowner's insurance claims related to that work. Before starting any project that touches your home's systems, check with your local building department. For structural concerns specifically, see our overview on what walls are actually holding up before removing anything.
[important_callout]Mold Requires More Than Surface Treatment
If you see recurring mold on drywall, wood framing, or other porous materials, surface cleaning alone is not a permanent fix. Persistent mold growth often signals an underlying moisture problem — such as a plumbing leak or inadequate ventilation — that must be corrected at the source. For large infestations, consult a licensed mold remediation professional.
60–80%
Typical kitchen remodel cost recouped at resale
Industry cost-vs-value analyses consistently show most kitchen renovations return less than their full cost, varying by region and project scope.
#1
Grease and fats as a drain blockage cause
Plumbing industry sources consistently rank fats, oils, and grease among the leading causes of residential and municipal sewer blockages.
Making Smarter Decisions Before You Start
The common thread running through most home improvement myths is that they offer a shortcut — a simpler version of reality that sounds plausible enough to act on without checking. The fix isn't to distrust all DIY instincts, but to slow down and verify before committing time and money.
A few habits that help: check with your local building department before any project touching electrical, plumbing, or structure; research recoup rates realistically before planning a renovation with resale in mind (our piece on curb appeal changes that affect perceived home value is a useful companion here); and treat any recurring moisture or mold issue as a systems problem, not a cosmetic one.
Smart home improvement is less about knowing every answer in advance and more about asking the right questions — including "Is what I've heard actually true?"