PRC LALE cheat sheet

Slope formula: percent slope = (vertical rise / horizontal run) x 100. A 1:12 ramp equals 8.33%.

Slope bands used in site planning: 0-3% level ground (lawns, courts, parking); 3-8% gentle (walks, lawns, drainage); 8-15% moderate (terraces, stepped walks); 15-25% steep (retaining walls, switchback paths); above 25% very steep, keep vegetated or engineer.

BP 344 accessibility rules: ramp maximum slope 1:12, clear width 1.20 m, landings every 6.00 m of run, handrails at 0.90 m and 0.70 m, turning space 1.50 m x 1.50 m.

Rational method Q = CiA sizes drainage for small catchments. Typical C values: lawn 0.15-0.25, gravel 0.35, asphalt 0.85-0.95; i is the design storm intensity for the time of concentration.

Contour spacing: horizontal distance between contours = contour interval / slope. Contours crossing a walkway align with slopes above about 4-5%; that condition calls for steps or a ramp.

Philippine solar geometry: latitude 5-20 degrees north, sun within about 23.5 degrees of the zenith. Horizontal fins work on north and south faces; east and west faces need vertical or egg-crate shading.

PD 1096 (National Building Code) sets minimum setbacks, site occupancy limits, and open space. RA 7160 devolves zoning to city and municipal councils, so the local zoning ordinance governs use, density, and buffer yards.

Site inventory overlays: geology and soils, slope and drainage, hydrology and flood lines, existing vegetation, climate and microclimate, circulation and access, views and vistas, utilities and easements, cultural features.

Fire access under RA 9514: fire lanes at least 6 m wide with adequate turning radius, and hydrants positioned within reach of every building.

Flexible pavement from bottom up: compacted subgrade, subbase, base course, wearing surface. Rigid pavement is a portland cement concrete slab resting on base or stabilized subgrade.

Concrete mix classes by volume: Class A 1:2:4 cement-sand-gravel, about 3,000 psi (20.7 MPa), used for footings, walks, and slabs; Class B 1:2.5:5 and Class C 1:3:6 for mass or nonstructural work.

Retaining wall types: gravity relies on mass, cantilever uses a stem with heel and toe slabs, counterfort adds transverse ribs for tall walls. Every wall needs weep holes, gravel drain, and filter fabric.

Earthwork: compute cut and fill by average end area or borrow pit method. A balanced site has zero net import or export; compacted fill occupies less volume than the same soil in loose condition.

Irrigation hydraulics: total head = static lift + friction loss + operating pressure. Keep velocity below about 1.5 m/s in PVC mains and size laterals so emitter pressure variation stays within 10-20%.

Site lighting rule of thumb: pole spacing is roughly 3-4 times mounting height. Bollards 0.6-1.0 m suit paths, 3-4 m poles suit drives, 6-9 m poles suit plazas and parking.

Concrete curing runs 7 days moist for normal work; slab and beam formwork is typically removed at 7-14 days, and backfilling against walls waits until the concrete has adequate strength.

Drainage details: catch basins at low points, pavement cross slope 1-2%, swales with 1-3% longitudinal slope, French drains using graded gravel wrapped in filter fabric.

Planting pit: two to three times the root ball width and no deeper than the root ball, with the root flare at or slightly above finished grade. Stake only when the root ball cannot hold the tree upright.

Root ball sizing rule of thumb: about 10-12 inches of ball diameter for every inch of trunk caliper in balled-and-burlapped nursery stock.

N-P-K roles: nitrogen drives shoot and leaf growth, phosphorus supports roots and flowering, potassium strengthens stems and stress tolerance. A soil test sets the application rate.

Pruning: thinning cuts remove a branch back to its origin or to a lateral and reduce density; heading cuts shorten branches and stimulate regrowth. Removing more than 25-30% of live canopy at once stresses the tree.

Turf: follow the one-third rule, mow at the tallest recommended height for the species, and recycle clippings. Scalping favors weeds and shallow roots.

Native Philippine trees for design: narra (Pterocarpus indicus), molave (Vitex parviflora), talisay (Terminalia catappa), banaba (Lagerstroemia speciosa), ilang-ilang (Cananga odorata).

Invasive plants to avoid in Philippine restoration work: water hyacinth (Eichhornia crassipes), Mikania micrantha, and Lantana camara; specify locally native pioneers instead.

Mangrove zonation from sea to land: Rhizophora with stilt roots on the seaward fringe, Sonneratia, then Avicennia with pneumatophores landward. Match species to tidal elevation.

Ecology applied to design: habitat patches linked by corridors reduce fragmentation effects, edge-to-interior ratio affects nesting success, and successional stage sets the maintenance intensity.

RA 9053, the Philippine Landscape Architecture Act of 2000, regulates licensure and practice; landscape plans and related documents for covered projects must carry the signature and seal of a licensed landscape architect.

The Professional Regulation Commission administers the licensure examination on the recommendation of the Board of Landscape Architecture, a three-member board appointed by the President for three-year terms.

RA 10912 (CPD Act of 2016) requires continuing professional development credits as a condition for renewing the PRC identification card, which is renewed every three years.

PALA, the Philippine Association of Landscape Architects, is the accredited professional organization and the Philippine member of IFLA; the PRC code of ethics governs professional conduct.

Ildefonso P. Santos Jr. was named National Artist in 2006 under the Architecture category, recognized for his landscape architecture work in parks, plazas, and institutional grounds.

Daniel Burnham's 1905 plans for Manila and Baguio, implemented with consulting architect William Parsons, produced Burnham Park and the Manila park and boulevard framework.

Kevin Lynch (The Image of the City, 1960) analyzed urban legibility through paths, edges, districts, nodes, and landmarks.

Ian McHarg (Design with Nature, 1969) introduced overlay suitability mapping; Frederick Law Olmsted and Calvert Vaux designed Central Park in 1858, and Olmsted later built Boston's Emerald Necklace.

Ebenezer Howard's 1898 Garden City concept, realized at Letchworth (1903) and Welwyn (1920), proposed limited-population towns ringed by agricultural greenbelts.